Abrasive Article For Ultra High Material Removal Rate Grinding Operations.

ABRASIVE ARTICLE FOR ULTRA HIGH SPEED GRINDING OPERATIONS OF MATERIAL REMOVAL

FIELD OF THE INVENTION

The following is directed to abrasive articles, and particularly agglomerated abrasive articles suitable for high speed grinding operations.

BACKGROUND OF THE INVENTION

Abrasive tools are generally formed to have abrasive grains contained within a binder material for material removal applications. Superrabrasive grains (for example, diamond or cubic boron nitride (CBN)) or sun-gel sintered sun-gel alumina abrasive grain (or not yet seeded), also referred to as microcrystalline alpha-alumina abrasive grain (MCA, for its acronym in English), can be used in such abrasive tools. The binder material may be organic materials, such as a resin, or an inorganic material, such as glass or vitrified material. In particular, abrasive tools agglomerated using a vitrified binder material and containing MCA grains or superabrasive grain are commercially useful for grinding.

Certain agglomerated abrasive tools, particularly those that use a binder material

Ref. 248530 vitrified, require high temperature formation processes, often in the order of 1100 ° C or higher, which can have detrimental effects on the abrasive grains of the MCA. In fact, it has been recognized that at such elevated temperatures necessary to form the abrasive tool, the binder material can react with the abrasive grains, particularly the MCA grains, and damage the integrity of the abrasives, reducing the performance and sharpness properties of the grain. As a result, the industry has migrated towards the reduction of the formation temperatures necessary to form the binder material to stop the high temperature degradation of the abrasive grains during the formation process.

For example, to reduce the amount of reaction between the MCA grain and vitrified bond, US Patent No. 4,543,107 describes a binder composition suitable for cooking at a temperature as low as about 900 ° C. In an alternative procedure, US Patent No. 4,898,597 describes a binder composition comprising at least 40% of fritted materials suitable for cooking at a temperature as low as about 900 ° C. Other agglomerated abrasive articles using binder materials capable of forming at temperatures below 1000 ° C, including US Patent No.

5,203,886, U.S. Patent No. 5,401,284, U.S. Patent No. 5,536,283, and U.S. Patent No. 6,702,867. Still, the industry continues to demand improved performance of such agglomerated abrasive articles.

The above vitreous binder materials are not necessarily suitable for high speed grinding operations. Typically, high speed grinding operations require vitreous agglomerated abrasive articles formed at sintering temperatures in excess of 1100 ° C, so that the abrasive article can withstand the forces applied during high speed grinding operations. The industry continues to demand improved agglomerated abrasive articles.

BRIEF DESCRIPTION OF THE FIGURES

The present description can be better understood, and its numerous features and advantages become apparent to those skilled in the art by referring to the accompanying figures.

FIG. 1 includes a graph of average power (kW) against material removal speed (mm³/ s / mm) for conventional agglomerated abrasive articles and an abrasive article according to one embodiment.

FIG. 2 includes a graph of ratio G (volume of material removed / volume of wheel wear) versus material removal speed (mm³/ s / mm) for conventional agglomerated abrasive articles and an abrasive article according to one embodiment.

FIG. 3 includes a graph of radial wheel wear (Ars in mm) against material removal speed (mm³/ s / mm) for conventional agglomerated abrasive articles and an abrasive article according to one embodiment.

FIG. 4 includes a graph of the edge radius (mm) against the material removal rate (mm³/ s / mm) for conventional agglomerated abrasive articles and an abrasive article according to one embodiment.

FIGS. 5 and 6 include illustrations of the loss of form between conventional agglomerated abrasives and an abrasive article according to one embodiment.

FIG. 7 includes a graph of the speed of removal of actual material versus the rate of removal of theoretical material for conventional agglomerated abrasive articles and an abrasive article according to one embodiment.

FIG. 8 includes a graph of surface roughness (Ra) against the speed of removal of material for conventional agglomerated abrasive articles and an abrasive article according to one embodiment.

FIG. 9 includes a graph of the maximum material removal rate (in³/ min / in) for conventional agglomerated abrasive articles and abrasive article according to one modality.

FIG. 10 includes a graph of average unit power (Hp / in) against material removal rate (in³/ min / in) for conventional agglomerated abrasive articles and abrasive articles according to one modality.

The use of the same reference symbols in different figures indicates similar or identical elements.

DETAILED DESCRIPTION OF THE INVENTION

The following is directed to agglomerated abrasive articles, which may be suitable for grinding and shaping work pieces. Notably, agglomerated abrasive articles of the embodiments herein may incorporate abrasive particles within a binder material. Suitable applications for use of the agglomerated abrasive articles of the embodiments herein include grinding operations, including, for example, centerless grinding, cylindrical grinding, crankshaft grinding, various surface grinding operations, bearing grinding operations and gears, trailed feed grinding and various tool shop applications.

According to one embodiment, the method of forming an agglomerated abrasive article of one embodiment can be initiated by forming a mixture of compounds and components suitable to form a binder material. The bond can be formed of compounds of inorganic material, such as oxide compounds. For example, a suitable oxide material may include silicon oxide (S1O2). According to one embodiment, the binder material can be formed of no more than about 62% by weight silicon oxide of the total weight of the binder material. In other embodiments, the silicon oxide content may be less, such as not more than about 60% by weight, not more than about 59% by weight, or even no more than about 58% by weight. Still, in certain embodiments the binder material can be formed of at least about 45% by weight, in the order of at least about 47% by weight, at least about 48% by weight, or even at least about 49% by weight, at least about 50% by weight, at least about 52% by weight of silicon oxide of the total weight of the binder material. It will be appreciated that the amount of silicon oxide may be within a range between any of the minimum and maximum percentages noted above.

The binder material can also incorporate a certain content of aluminum oxide (AI2O3). For example, the binder material may include at least about 9% by weight of aluminum oxide of the total weight of the binder material. In other embodiments, the amount of aluminum oxide may be at least about 10% by weight, at least about 11% by weight, or even about 12% by weight. In certain cases, the binder material may include an amount of aluminum oxide that is not more than about 20% by weight, not more than about 18% by weight, not more than about 16% by weight, or even not more than about 15% by weight of the total weight of the binder material. It will be appreciated that the amount of aluminum oxide may be within a range between any of the minimum and maximum percentages noted above.

In certain cases, the binder material can be formed from a particular relationship between the amount of silicon oxide as measured by weight percentage versus the amount of aluminum oxide as measured by weight percentage. For example, the ratio of silica to alumina can be described by dividing the percentage by weight of silicon oxide by the percentage by weight of aluminum oxide within the binder material. According to one embodiment, the ratio of silicon oxide to aluminum oxide may be no greater than about 5. In other cases, the ratio of silicon oxide to aluminum oxide within the binder material may be no greater than about 4.8, not greater than approximately 4.6, not greater than approximately

4.5. Still, the binder material can be formed such that the ratio of percent by weight of silicon oxide to percent by weight of aluminum oxide is at least about 1.8, such as at least about 2, such as at least about 2.2, or even at least about 2.5. It will be appreciated that the total amount of aluminum oxide and silicon oxide may be within a range between any of the minimum and maximum values ​​noted above.

According to one embodiment, the binder material can be formed of a certain boron oxide content (B2O3). For example, the binder material may incorporate no more than about 20% by weight of boron oxide of the total weight of the binder material. In other cases, the amount of boron oxide may be less, such as not more than about 19% by weight, not more than about 18% by weight, not more than about 17% by weight, or even not more than about 16 % in weigh. Still, the binder material can be formed of at least about 10% by weight, such as at least about 12% by weight, at least about 13% by weight, or even at least about 14% by weight of boron oxide of the weight Total binder material. It will be appreciated that the amount of boron oxide may be within a range between any of the minimum and maximum percentages noted above.

According to one embodiment, the binder material can be formed such that the total content (i.e., sum) of the percent by weight of boron oxide and percent by weight of silicon oxide within the binder material may be no greater than approximately 80% by weight of the total weight of the binder material. In other cases, the total content of silicon oxide and boron oxide may be not more than about 78% by weight, such as not more than about 76% by weight, or even no more than about 74% by weight. According to a particular embodiment, the total weight percentage content of silicon oxide and boron oxide may be at least about 60% by weight, such as at least about 66% by weight, at least about 6 8% by weight , or even at least about 7% by weight of the total weight of the binder material. It will be appreciated that the total weight percentage of silicon oxide and boron oxide within the binder material may be within a range between any of the minimum and maximum percentages noted above.

In addition, in particular cases, the amount of silicon oxide may be greater than the amount of boron oxide within the binder material, as measured by weight percentage. Notably, the amount of silicon oxide can be at least about 1.5 times greater, at least about 1.7 times greater, at least about 1.8 times greater, at least about 1.9 times greater, at least about 2.0 times greater, or even at least about 2.5 times greater than the amount of boron oxide. Still, in one embodiment, the binder material may include an amount of silicon oxide that is not more than about 5 times greater, such as not more than about 4.5 times greater, or even no more than about 4 times greater than the amount of boron oxide. It will be appreciated that the difference in the amount of silicon oxide compared to the amount of boron oxide may be within a range between any of the minimum and maximum values ​​noted above.

According to one embodiment, the binder material can be formed of at least one alkali oxide (R2O) compound, wherein R represents a metal selected from elements of Group IA of the Periodic Table of the Elements. For example, the binder material may be formed of an alkali oxide (R2O) compound from the group of compounds including lithium oxide (L12O), sodium oxide (Na2Ü), potassium oxide (K2O), and cesium oxide ( Cs2O), and a combination thereof.

According to one embodiment, the binder material can be formed from a total content of alkali oxide compounds of no more than about 20% by weight of the total weight of the binder material. For other abrasive articles bonded according to the embodiments herein, the total content of alkali oxide compounds may be not more than about 19% by weight, not more than about 18% by weight, not more than about 17% by weight , not more than about 16% by weight, or even not more than about 15% by weight. Still, in one embodiment, the total content of alkali oxide compounds within the binder material may be at least about 5% by weight, such as at least about 7% by weight, at least about 9% by weight, at least about 11 % by weight, or even at least about 12% by weight. It will be appreciated that the binder material may include a total content of alkali oxide compounds within a range between any of the minimum and maximum percentages noted above.

According to a particular embodiment, the binder material may be formed of no more than about 4 individual alkali oxide (R2O) compounds as noted above. In fact, certain binder materials can incorporate no more than about 3 alkali oxide compounds into the binder material. In a particular embodiment, the binder material can be formed of at least 2 alkali oxide compounds.

According to a particular embodiment, the amount of sodium oxide may be greater than the content (weight percentage) of lithium oxide or potassium oxide. In more particular cases, the total sodium oxide content as measured by weight percentage may be greater than the sum of the lithium oxide and potassium oxide content as measured by weight percentage. In addition, in one embodiment, the amount of lithium oxide may be greater than the content of potassium oxide.

According to one embodiment, the total amount of alkali oxide compounds as measured in weight percent that forms the binder material may be less than the amount (as measured in weight percent) of boron oxide within the binder material. In fact, in certain cases, the total weight percentage of the alkali oxide compounds compared to the total weight percentage of boron oxide (R2O / B2O3) within the binder material may be within a range between about 0.7 to about 1.5, such as within a range between approximately 0.7 and approximately 1.3, or even within a range between approximately 0.7 and approximately

1.1.

The binder material can be formed from a certain amount of alkaline earth compounds (RO), where R represents an element of Group HA of the Periodic Table of the Elements. For example, the binder material may incorporate alkaline earth oxide compounds such as calcium oxide (CaO), magnesium oxide (MgO), barium oxide (BaO), or even strontium oxide (SrO).

According to one embodiment, the binder material can be formed of no more than about 3% by weight of alkaline earth oxide compounds of the total weight of the binder material. In still other cases, the binder material may be formed from less alkaline earth oxide compounds, such as in the order not greater than about 2.8% by weight, not greater than about 2.2% by weight, not greater than about 2% by weight, not greater than approximately 1.8% by weight, not greater than approximately 1.3% by weight, or even not greater than approximately 1% by weight. Still, according to one embodiment, the binder material may contain a content of one or more alkaline earth oxide compounds of at least about 0.2% by weight, such as at least about 0.3% by weight, at least about 0.5% by weight, or even at least about 0.6% by weight of the total weight of the binder material. It will be appreciated that the amount of alkaline earth oxide compounds within the binder material may be within a range between any of the minimum and maximum percentages noted above.

According to one embodiment, the binder material can be formed from no more than about 3 different alkaline earth oxide compounds. In fact, the binder material may contain no more than 2 different alkaline earth oxide compounds, or even no more than about 1 alkaline earth oxide compound.

In one embodiment, the binder material may include an amount of calcium oxide that is greater than an amount of magnesium oxide. In addition, the amount of calcium oxide within the binder material may be greater than the content of any of the other alkaline earth oxide compound present within the binder material.

The binder material may be formed from a combination of alkaline oxide (R2O) compounds and alkaline earth oxide (RO) compounds such that the total content is not greater than about 20% by weight of the total weight of the binder material. In other embodiments, the total content of alkali oxide compounds and alkaline earth oxide compounds within the binder material may be not more than about 19% by weight, such as not more than about 18% by weight, or even no more than about 17 % in weigh. However, in certain embodiments, the total content of alkali oxide compounds and alkaline earth compounds present within the binder material may be at least about 7% by weight, such as at least about 8% by weight, such as at least about 10% by weight, at least about 11% by weight, or even at least about 12% by weight. It will be appreciated that the binder material may have a total content of alkali oxide compounds and alkaline earth compounds within a range between any of the minimum and maximum percentages noted above.

According to one embodiment, the binder material can be formed such that the total content of alkali oxide compounds present within the binder material is greater than the total content of alkaline earth oxide compounds. In a particular embodiment, the binder material may be formed such that the ratio of total content (in weight percent) of alkali oxide compounds compared to the total weight percent of alkaline earth oxide compounds (R2Ü: RO) is within a range between about 5: 1 and about 18: 1. In other embodiments, the ratio of the total weight percentage of the alkali oxide compounds to the total weight percentage of the alkaline earth oxide compounds present within the binder material may be within a range between about 6: 1 and about 17: 1, such as within a range between about 7: 1 and about 17: 1, or even with a range between about 8: 1 and about 17: 1.

According to one embodiment, the binder material may be formed of no more than about 3% by weight phosphorus oxide of the total weight of the binder material. In certain other cases, the binder material may contain no more than about 2.5% by weight, such as no more than about 2% by weight, no more than about 1.5% by weight, no more than about 1% by weight, no more of about 0.8% by weight, not more than about 0.5% by weight, or even not more than about 0.2% by weight of phosphorus oxide of the total weight of the binder material. In fact, in certain cases, the binder material may be essentially free of phosphorous oxide. Suitable phosphorus oxide contents may facilitate certain characteristics and performance properties of grinding as described herein.

According to one embodiment, the binder material can be formed from a composition comprising no more than about 1% by weight of certain oxide compounds, including for example, oxide compounds such as MnCh, ZrSiCh, C0AI2O4, and MgO. In fact, in particular embodiments, the binder material can be essentially free of any oxide compound including MnCh, ZrSiCh, C0AI2O4, and MgO.

In addition to the binder materials placed within the mixture, the formation process of the agglomerated abrasive article may also include the incorporation of a certain abrasive particulate material. In certain cases, the mixture used to form the abrasive article may include a combination of different types of abrasive particulate material, including, for example, a combination of non-agglomerated abrasive particles and abrasive agglomerates. The non-agglomerated abrasive particles may be separate particulate material and separate from the abrasive agglomerates. The non-agglomerated abrasive particles can be individual abrasive particles that define a crystalline or polycrystalline material. Abrasive agglomerates can be an aggregate of abrasive particles agglomerated together and contained within a binder.

Non-agglomerated abrasive particles may include an oxide, carbide, nitride, boride, and a combination thereof. Abrasive particles can be a superabrasive material. An exemplary oxide material suitable for use in non-agglomerated abrasive particles is alumina. According to a particular embodiment, the non-agglomerated abrasive particles can consist essentially of alumina, and more particularly, consist essentially of microcrystalline alumina. The non-agglomerated abrasive particles may contain the same material as the abrasive particles contained in the abrasive agglomerates.

The non-agglomerated abrasive particles can have an average particle size that is not larger than about 1,050 microns. In other embodiments, the average particle size of the non-agglomerated abrasive particles may be smaller, such as in the order of no more than 800 microns, no more than about 600 microns, no more than about 400 microns, no more than about 250 microns , not greater than about 225 microns, no more than about 200 microns, no more than about 175 microns, no more than about 150 microns, or even no more than about 100 microns. Still, the average particle size of the non-agglomerated abrasive particles can be at least about 1 mill, such as at least 5 microns, at least about 10 microns, at least about 20 microns, at least about 30 microns, or even at least approximately 50 microns, at least about 60 microns, at least about 70 microns, or even at least about 80 microns. It will be appreciated that the average particle size of the non-agglomerated abrasive particles may be in a range between any of the minimum and maximum values ​​indicated above.

In further reference to non-agglomerated abrasive particles using microcrystalline alumina, it will be appreciated that microcrystalline alumina can be formed from grains (i.e., crystallites) that have an average grain size that is sub-micron size. In fact, the average grain size of microcrystalline alumina may be no larger than about 1 micron, such as no more than about 0.5 microns, no more than about 0.2 microns, no more than about 0.1 microns, or even no more than about 0.08 you love Still, in one case, the average grain size may be at least about 0.01 microns.

In reference to abrasive agglomerates, non-agglomerated abrasive particles can be combined with abrasive agglomerates to form the abrasive article. Abrasive agglomerates comprise abrasive particles contained in a binder. The abrasive particles of the abrasive agglomerates can be an oxide, carbide, nitride, boride, and a combination thereof. The abrasive particles of the abrasive agglomerates can be a superabrasive material. In one case, the abrasive particles of the abrasive agglomerates may include alumina, and may consist essentially of alumina, and more particularly, may consist essentially of microcrystalline alumina.

According to a particular embodiment, abrasive agglomerates can be made by forming a mixture that includes a binder material and abrasive particles. Depending on the binder material, the mixture can be treated to form abrasive agglomerates. For example, for a binder material comprising an inorganic material, such as an oxide-based material (for example, vitreous material), further treatment of the mixture may include heat treatment, and particularly treatment in a rotary kiln. to create abrasive agglomerates. After treatment, the resulting material can be crushed as necessary to achieve a particular size and shape of the abrasive agglomerate.

In an exemplary and non-limiting mode, abrasive agglomerates may contain no more than about 80% by volume of abrasive particles of the total volume of the abrasive agglomerate. In other cases, abrasive agglomerates can be formed to contain no more than about 70% by volume, no more than about 65% by volume, no more than about 60% by volume, no more than about 55% by volume, or even no more than about 50% by volume of abrasive particles of the total volume of abrasive agglomerates. Still, in particular cases, abrasive agglomerates can be formed to include at least about 10% by volume, such as at least about 2% by volume, at least about 25% by volume, or even at least about 30% by volume. of abrasive particles of the total volume of abrasive agglomerates. It will be appreciated that the content of abrasive particles within the abrasive agglomerates may be within a range between any of the minimum and maximum values ​​noted above.

In addition, in one embodiment, the abrasive particles of the abrasive agglomerates can have an average particle size of at least about 10 microns. In still other agglomerates of the embodiments herein, the average particle size of the abrasive particles may be at least about 2 0 microns, such as at least about 50 microns. Still, the abrasive particles may be no greater than about 250 microns, no greater than about 200 microns, or even nc greater than about 180 microns. It will be appreciated that the average particle size of the abrasive particles within the abrasive agglomerates may be within a range between any of the minimum and maximum values ​​noted above.

Abrasive particles of the abrasive agglomerate may include microcrystalline alumina which may have an average grain size as described in the embodiments herein.

Abrasive agglomerates can have a particular size. For example, abrasive agglomerates may have an average agglomerate size, which is a measure of the longest size of the agglomerate, of at least about 50 microns, such as at least about 80 microns, at least about 100 microns, at least about 150 microns, at least about 200 microns, at least about 250 microns, at least about 500 microns, or at least about 600 microns. Still, according to a particular embodiment, abrasive agglomerates can have an average agglomerate size not greater than about 2 mm, such as not greater than about 1 mm, or even not greater than about 0.8 mm. It will be appreciated that the average agglomerate size may be within a range between any of the minimum and maximum values ​​indicated above.

As described herein, abrasive agglomerates may have abrasive particles contained in a binder. According to a non-limiting modality, the binder can be an inorganic material, an organic material, and a combination thereof. Some exemplary binders include vitrified material, organic material, crystalline material, and a combination thereof. In a particular case, the binder may be an oxide-based vitrified material having a facilitating formation of particular composition of an abrasive article in accordance with embodiments herein.

According to one embodiment, the binder may be formed of silicon oxide (S1O2), and in particular, it may contain no more than about 62% by weight of silicon oxide of the total weight of the binder. In other embodiments, the binder may be formed of a silicon oxide content not greater than about 60% by weight, not greater than about 59% by weight, or even not greater

<td colspan="2">that approximately 58% in</td><td>weight. Without</td><td>embargo,</td><td colspan="2">in certain</td>

<td>modalities the</td><td>binder</td><td>It can</td><td>form of</td><td>to the</td><td>less</td>

<td>approximately</td><td>45% in</td><td>weight such</td><td>how</td><td>to the</td><td>less</td>

<td>approximately</td><td>50% in</td><td>weight 0</td><td>even</td><td>to the</td><td>less</td>

<td>approximately</td><td>52% by weight</td><td>of oxide</td><td colspan="2">silicon</td><td>weight</td>

Total binder. It will be appreciated that the amount of silicon oxide may be within a range between any of the minimum and maximum percentages noted above.

The binder may also incorporate a certain content of aluminum oxide (AI2O3), such as at least about 9% by weight, at least about 10% by weight, or even about 12% by weight of the total weight of the binder. In certain cases, the binder may include an amount of aluminum oxide that is not more than about 20% by weight, not more than about 16% by weight, or even not more than about 14% by weight of aluminum oxide. It will be appreciated that the amount of aluminum oxide may be within a range between any of the minimum and maximum percentages noted above.

In certain cases, the binder can be formed from a particular relationship between the amount of silicon oxide as measured in weight percent versus the amount of aluminum oxide as measured in weight percent. For example, the ratio of silica to alumina can be described by dividing the percentage by weight of silicon oxide by the percentage by weight of aluminum oxide within the binder material. According to one embodiment, the ratio of silicon oxide to aluminum oxide may be not more than about 5 or not more than about 4.5. Still, the binder can be formed such that the ratio of percent by weight of silicon oxide to percent by weight of aluminum oxide is at least about 1.8, such as at least about 2.2, or even at least about 2.5. It will be appreciated that the total amount of aluminum oxide and silicon oxide may be within a range between any of the minimum and maximum values ​​noted above.

According to one embodiment, the binder can be formed of a certain content of boron oxide (B2O3). For example, the binder may be formed of no more than about 20% by weight of boron oxide, such as no more than about 18% by weight of the total weight of the binder. Still, the binder can be formed of at least about 10% by weight or even at least about 12% by weight of boron oxide of the total weight of the binder. It will be appreciated that the amount of boron oxide may be within a range between any of the minimum and maximum percentages noted above.

According to one embodiment, the binder can be formed such that the total content (i.e., sum) of the percent by weight of boron oxide and percent by weight of silicon oxide within the binder may be no more than about 80% by weight of the total weight of the binder. In other cases, the total content of silicon oxide and boron oxide may be not more than about 78% by weight, such as not more than about 76% by weight. According to a particular embodiment, the total weight percentage content of silicon oxide and boron oxide may be at least about 55% by weight, such as at least about 58% by weight, or even at least about 62% by weight. weight of the total weight of the binder. It will be appreciated that the total weight percentage of silicon oxide and boron oxide within the binder may be within a range between any of the minimum and maximum percentages noted above.

In addition, in particular cases, the amount of silicon oxide may be greater than the amount of boron oxide within the binder, as measured by weight percentage. Notably, the amount of silicon oxide can be at least about 1.5 times greater, at least about 1.7 times greater, at least about 1.8 times greater, or even at least about 2.5 times greater than the amount of boron oxide. Still, in one embodiment, the binder may include an amount of silicon oxide that is less than about 5 times greater, such as no more than about 4.5 times greater, or even no more than about 4 times greater than the amount of oxide of boron. It will be appreciated that the difference in the amount of silicon oxide compared to the amount of boron oxide may be within a range between any of the minimum and maximum values ​​noted above.

According to one embodiment, the binder can be formed of at least one alkali oxide compound (R₂0), where R represents a metal selected from the elements of Group IA of the Periodic Table of the Elements. For example, the binder can be formed of an alkali oxide compound (R₂0) from the group of compounds including lithium oxide (L12O), sodium oxide (Na20), potassium oxide (K2O), and cesium oxide (CS2O), and a combination thereof.

According to one modality, the binder is

I can form a total content of alkali oxide compounds of no more than about 2% by weight of the total weight of the binder. For other agglomerates according to embodiments herein, the total content of alkali oxide compounds may be not more than about 19% by weight, not more than about 18% by weight, not more than about 17% by weight, not greater that approximately 16% by weight, or even not greater than approximately 15% by weight. Still, in one embodiment, the total content of alkali oxide compounds within the agglomerate binder can be at least about 5% by weight, such as at least about 7% by weight, or even at least about 9% by weight. It will be appreciated that the binder may include a total content of alkali oxide compounds within a range between any of the minimum and maximum percentages noted above.

According to a particular embodiment, the binder can be formed from no more than about 4 individual alkaline oxide (R2O) compounds as noted above. In fact, certain binders can use no more than about 3 alkali oxide compounds, such as 2 alkali oxide compounds.

According to a particular embodiment, the amount of sodium oxide present in the binder of the agglomerates may be greater than the content (weight percentage) of lithium oxide or potassium oxide. In more particular cases, the total sodium oxide content as measured by weight percentage may be greater than the sum of the lithium oxide and potassium oxide content as measured by weight percentage. In addition, in one embodiment, the amount of lithium oxide may be greater than the content of potassium oxide.

According to one embodiment, the total amount of alkali oxide compounds as measured in percent by weight that forms the binder may be less than the amount (as measured in percent by weight) of boron oxide within the binder. In fact, in certain cases, the total weight percentage of the alkali oxide compounds compared to the total weight percentage of boron oxide (R2O / B2O3) within the binder may be within a range between about 0.7 to about 1.5 , such as within a range between about 0.7 and about 1.3, or even within a range between about 0.7 and about 1.1.

The binder of the abrasive agglomerates can be formed from a certain amount of alkaline earth compounds (RO), where R represents an element of Group IIA of the Periodic Table of the Elements. For example, the binder may incorporate alkaline earth oxide compounds, such as calcium oxide (CaO), magnesium oxide (MgO), barium oxide (BaO), or even strontium oxide (SrO).

According to one embodiment, the binder can be formed of no more than about 3% by weight of alkaline earth oxide compounds of the total weight of the binder. In still other cases, the binder may be formed from less alkaline earth oxide compounds, such as in the order of not more than about 2.8% by weight, not greater than about 2.2% by weight, not greater than about 2% by weight, not greater than approximately 1.8% by weight, not greater than approximately 1.3% by weight, or even not greater than approximately 1% by weight. However, according to one embodiment, the binder may contain a total content of one or more alkaline earth oxide compounds of at least about 0.2% by weight or even at least about 0.6% by weight of the total weight of the binder. It will be appreciated that the amount of alkaline earth oxide compounds within the binder may be within a range between any of the minimum and maximum percentages noted above.

According to one embodiment, the binder of the abrasive agglomerates can be formed from no more than about 3 different alkaline earth oxide compounds, such as no more than 2 different alkaline earth oxide compounds, or even no more than 1 alkaline earth oxide compound.

In one embodiment, the binder may include an amount of calcium oxide that is greater than an amount of magnesium oxide. In addition, the amount of calcium oxide within the binder material may be greater than the content of any of the other alkaline earth oxide compounds present within the binder.

The binder can be formed from a combination of alkaline oxide (R2O) compounds and alkaline earth oxide (RO) compounds such that the total content is not greater than about 2% by weight of the total weight of the binder. In other embodiments, the total content of alkali oxide compounds and alkaline earth oxide compounds within the binder may be not more than about 19% by weight, such as not more than about 18% by weight, or even not more than about 17% in weigh. However, in certain embodiments, the total content of alkali oxide compounds and alkaline earth compounds present within the binder material may be at least about 7% by weight, such as at least about 8% by weight, such as at least about 9% by weight, or even at least about 10% by weight. It will be appreciated that the binder material may have a total content of alkali oxide compounds and alkaline earth compounds within a range between any of the minimum and maximum percentages noted above.

According to one embodiment, the binder of the abrasive agglomerates can be formed such that the total content of alkali oxide compounds present within the binder material is greater than the total content of alkaline earth oxide compounds. In a particular embodiment, the binder can be formed such that the ratio of total content (in weight percent) of alkali oxide compounds compared to the total weight percent of alkaline earth oxide compounds (RsOzRO) is within a range between about 5: 1 and about 25: 1. In other embodiments, the ratio of the total weight percentage of the alkali oxide compounds to the total weight percentage of the alkaline earth oxide compounds present within the binder may be within a range between about 6: 1 and about 23: 1, such as within a range between about 7: 1 and about 22: 1, or even within a range between about 8: 1 and about

20:1.

According to one embodiment, the binder can be formed of no more than about 3% by weight phosphorus oxide of the total weight of the binder. In certain other cases, the binder may contain no more than about 2.5% by weight, such as no more than about 2% by weight, no more than about 1.5% by weight, no more than about 1% by weight, no more than about 0.8% by weight, not more than about 0.5% by weight, or even not more than about 0.2% by weight of phosphorus oxide of the total weight of the binder. In fact, in certain cases, the binder may be essentially free of phosphorus oxide. Suitable phosphorus oxide contents may facilitate certain characteristics and performance properties of grinding as described herein.

Abrasive agglomerates may contain a particular amount of binder to facilitate the formation of an agglomerated abrasive body in accordance with the embodiments herein. For example, the amount of binder may be no more than about 20% by volume of the total volume of the abrasive agglomerate. In still other cases, the amount of binder may be no more than about 18% by volume, no more than about 15% by volume, no more than about 12% by volume, no more than about 10% by volume, no more than approximately 8% by volume, not greater than approximately 5% by volume, not greater than approximately 4% by volume, or even not greater than approximately 3% by volume. Still, according to a particular embodiment, abrasive agglomerates can be formed to include at least about 0.5% by volume, at least about 0.8% by volume, at least about 1% by volume, or even at least about 1.3 % by volume of binder of the total volume of the abrasive agglomerate. It will be appreciated that the amount of binder within the abrasive agglomerates may be within a range between any of the minimum and maximum percentages noted above.

Abrasive agglomerates may contain a particular amount of porosity to facilitate the formation of an abrasive body in accordance with the embodiments herein. For example, the amount of porosity within the abrasive agglomerates can be at least about 15% by volume of the total volume of the abrasive agglomerate. In another embodiment, the amount of porosity can be at least about 18% by volume, at least about 20% by volume, at least about 25% by volume, at least about 30% by volume, at least about 40% by volume, at least about 45% by volume, at least about 50% by volume, at least about 55% by volume, or even at least about 57% by volume. Still, according to particular embodiments, the porosity of the abrasive agglomerates can be no more than about 85% by volume, no more than about 80% by volume, no more than about 75% by volume, or even no more than about 70 % by volume of the total volume of abrasive agglomerates.

Abrasive agglomerates can be formed to have a particular shape. For example, certain abrasive agglomerates may have an aspect ratio, which is a measure of the length (i.e., the longest dimension) to the width (shortest dimension measured perpendicular to the length) of no more than about 3: one. In other cases, the aspect ratio of abrasive agglomerates may be no greater than about 2: 1, no greater than about 1.7: 1, no greater than about 1.5: 1, or even no greater than about 1.3: 1. In a particular embodiment, the abrasive article includes abrasive agglomerates that are substantially equiaxial particles.

Additionally, the agglomerated abrasive body may be formed from a mixture that includes an additive, including, for example, one or more inorganic materials, including, for example, oxides, and particularly may include crystalline or amorphous phases of zirconia, silica, titania, and a combination thereof.

In certain cases, the additive may include one or more pore forming agents. Some suitable pore forming agents may include organic materials, natural materials, polymeric materials, inorganic materials, and a combination thereof. According to one embodiment, the body can be formed of one or more pore-forming agents, such as alumina bubbles, mullite bubbles, hollow glass spheres, hollow ceramic spheres, hollow polymer spheres, polymers, organic compounds, materials Fibrous, naphthalene, paradichlorobenzene (AP), husks, wood, and a combination thereof. In more particular cases, the agglomerated abrasive body can be formed from a combination of at least about 2 different pore-forming agents, wherein the body was formed from a combination of bubble material and an organic-based pore-forming agent. The organic-based pore forming agent can be nutshell.

In certain embodiments, the agglomerated abrasive body may be formed of a pore forming agent in an amount of at least about 1% by weight of the total weight of the mixture. In other cases, the content of the pore-forming agent that constitutes the mixture from which the agglomerated abrasive body is formed can be at least about 2% by weight, such as at least about

3% by weight, at least about 4% by weight, or even at least about 5% by weight. Still, the total content of the pore-forming agent used to form the agglomerated abrasive body may be no more than about 5 15% by weight, no more than about 12% by weight, no more than about 10% by weight, no greater than approximately 9% by weight of the total weight of the mixture. It will be appreciated that the above amounts may represent the amount of alumina bubbles within the mixture used to form the agglomerated abrasive body. It will be further appreciated that the total content of the pore-forming agent within the mixture to form the agglomerated abrasive body may be within a range between any of the minimum and maximum percentages noted above.

After the mixture is properly formed, the mixture can be shaped. Suitable forming processes may include casting, molding, pressing, extrusion, and a combination thereof. In particular cases, the shaping includes pressing operations 20 and / or molding operations and a combination thereof.

For example, in one embodiment, the mixture can be formed by cold pressing the mixture into a mold to form a raw body.

After the raw body is properly formed, the raw body can be cooked at a particular temperature to facilitate the formation of an abrasive article having a suitable binder material. Notably, for embodiments herein that use a vitreous phase binder material, the cooking operation can be performed at a cooking temperature that is less than about 1000 ° C. In particular embodiments, the cooking temperature may be less than about 980 ° C, such as less than about 950 ° C, and particularly within a range between about 800 ° C and 950 ° C. It will be appreciated that particularly low cooking temperatures can be used with the binder components noted above in such a way that excessively high temperatures are avoided and therefore the degradation of the abrasive particles during the forming process is limited.

According to a particular embodiment, the agglomerated abrasive body comprises a binder material having a vitreous phase material. In particular cases, the binder material may be a single phase vitreous material.

The finally formed agglomerated abrasive body can have a particular content of binder material, abrasive particles, and porosity that can facilitate improved performance. For example, the agglomerated abrasive article body may have a porosity of at least about 42% by volume of the total volume of the agglomerated abrasive body. In other embodiments, the amount of porosity may be greater such as at least about 4 3% by volume, such as at least about 44% by volume, at least about 45% by volume, at least about 46% by volume, at least about 48% by volume, at least about 50% by volume, or even at least about 52% by volume of the total volume of the agglomerated abrasive body. According to one embodiment, the agglomerated abrasive body may have a porosity that is not more than about 70% by volume, such as not more than about 65% by volume, not more than about 63% by volume, not more than about 60% by volume, not greater than about 58% by volume of the total volume of the agglomerated abrasive body. It will be appreciated that the agglomerated abrasive body may have a porosity within a range between any of the minimum and maximum percentages indicated above.

In addition, in particular cases, the agglomerated abrasive body may have a portion of the porosity that is interconnected porosity, wherein the interconnected porosity is defined as an interconnected network of channels that extend through the body and open to the external surface of the body. chipboard abrasive. According to one modality, at least about 5% of the total porosity volume is interconnected porosity. In other cases, the interconnected porosity content may be greater, such as at least about 10%, at least about 20%, at least about 30%, at least about 40%, or even at least about 50% of the porosity total. Still, in particular embodiments, the amount of interconnected porosity may be no more than about 95%, such as no more than about 90%, or no more than about 85% of the total volume of the porosity. It will be appreciated that the agglomerated abrasive body may have an interconnected porosity content within a range between any of the minimum and maximum percentages noted above.

In one embodiment, the agglomerated abrasive body may contain a lower content (% by volume) of binder material compared to the content of porosity and abrasive particles. For example, the agglomerated abrasive body may have no more than about 15% by volume of binder material of the total volume of the agglomerated abrasive body. In other cases, the agglomerated abrasive body can be formed in such a way that it contains no more than about 12% by volume, no more than about 10% by volume, or even no more than about 9% by volume, no more than about 8 % by volume, not more than about 7% by volume, or even not more than about 6.5% by volume of binder material of the total volume of the agglomerated abrasive body. In a particular case, the agglomerated abrasive body may have at least about 1% by volume, such as at least about 2% by volume, in the order of at least about 3% by volume, or even at least about 4% by volume. of binder material of the total volume of the agglomerated abrasive body. It will be appreciated that the agglomerated abrasive body may have a content of binder material within a range between any of the minimum and maximum percentages noted above.

The agglomerated abrasive body may contain a particular content of abrasive particulate material that can facilitate improved performance. The abrasive particulate material may include non-agglomerated abrasive particles, abrasive agglomerates and secondary abrasive materials and fillers.

According to one embodiment, the agglomerated abrasive body may have a total content of abrasive particulate material of at least about 35% by volume of the total volume of the agglomerated abrasive body. In certain other cases, the total content of abrasive particulate material may be greater, such as at least about 37% by volume, at least about 39% by volume, at least about 40% by volume, at least about 42% by volume, or even at least about 44% by volume. According to another particular embodiment, the agglomerated abrasive body can be formed such that it has no more than about 55% by volume, no more than about 54% by volume, no more than about 52% by volume, no more than about 50 % by volume, not more than about 48% by volume, or even not more than about 46% by volume of abrasive particulate material of the total volume of the agglomerated abrasive body. It will be appreciated that the content of abrasive particulate material within the agglomerated abrasive body may be within a range between any of the minimum and maximum percentages noted above.

1.5 In a particular case, the content (% by volume) of abrasive agglomerates may be greater than a content (% by volume) of non-agglomerated abrasive particles. For example, the body can be formed entirely of abrasive agglomerates and contain non-agglomerated abrasive particles.

Alternatively, the amount (% by volume) of abrasive agglomerates may be less than a content (% by volume) of non-agglomerated abrasive particles. Still, in another particular embodiment, the amount (% by volume) of abrasive agglomerates can be substantially equal to (within 5%) the content (% by volume) of non-agglomerated abrasive particles.

In certain exemplary agglomerated abrasive bodies, the amount of abrasive agglomerates and non-agglomerated abrasive particles can be described by an abrasive particulate ratio (AP_p: AP_agg) within a range between 3: 1 and approximately 1: 3, where AP_P represents an amount (% by volume) of abrasive particles present in the body and AP_agg It represents a quantity (% by volume) of abrasive agglomerates present in the body. In other cases, the abrasive particulate ratio (AP_p: AP_agg) may be within a range between approximately 2.8: 1 and approximately 1: 2.8, such as within a range between approximately 2.6: 1 and approximately 1: 2.6, within a range between approximately 2.4: 1 and approximately 1: 2.4, within a range between approximately 2.2: 1 and approximately 1: 2.2, within a range between approximately 2: 1 and approximately 1: 2, within a range between approximately 1.8: 1 and approximately 1: 1.8, within a range between about 1.6: 1 and about 1: 1.6, or even within a range between about 1.4: 1 and about 1: 1.4.

According to a particular embodiment, the body may have a content of abrasive agglomerates of at least about 10% by volume of the total body volume. Still, the content of abrasive agglomerates may be greater, such as at least about 15% by volume, at least about 20% by volume, at least about 25% by volume, at least about 30% by volume, or even at least about 32% by volume of total body volume. However, in a particular case, abrasive agglomerates may be present in an amount not greater than about 80% by volume, such as not more than about 70% by volume, not more than about 65% by volume, not more than about 60% by volume, not greater than approximately 55% by volume, not greater than approximately 50% by volume, not greater than approximately 45% by volume, or even not greater than approximately 42% by volume. It will be appreciated that the content of abrasive agglomerates within the agglomerated abrasive body may be within a range between any of the minimum and maximum percentages indicated above.

In one embodiment, the body may have a content of non-agglomerated abrasive particles of at least about 10% by volume of the total body volume. Still, the content of non-agglomerated abrasive particles may be greater, such as at least about 15% by volume, at least about 20% by volume, at least about 25% by volume, at least about 30% by volume, or even at minus approximately 32% by volume of the total body volume. However, in a particular case, the non-agglomerated abrasive particles may be present in an amount not greater than about 80% by volume, such as not more than about 70% by volume, not more than about 65% by volume, not greater that about 60% by volume, not more than about 55% by volume, not more than about 50% by volume, not more than about 45% by volume, or even not more than about 42% by volume. It will be appreciated that the content of non-agglomerated abrasive particles within the agglomerated abrasive body may be within a range between any of the minimum and maximum percentages noted above.

It will be reasonably understood that the total content of the component phases (for example, abrasive particulate material, porosity, binder, fillers, etc.) of the agglomerated abrasive body adds up to and does not exceed 100%.

Generally, the phase contents of conventional agglomerated abrasive articles are limited, typically have a maximum porosity within a range between about 40% by volume and 51% by volume, an abrasive particle content of between about 42% by volume to 50% by volume, and a binder content of between about 10 to 20% by volume. Conventional agglomerated abrasive articles typically have a maximum porosity content of 50% by volume or less because grinding applications require an agglomerated abrasive body that has sufficient strength to deal with excessive forces encountered during high speed grinding, and highly porous agglomerated abrasive bodies have not previously been able to resist forces.

High speed grinding applications are typically considered performed at operating speeds of 60 m / s or greater. As used herein, ultra high speed material removal grinding operations (UHMRR) are grinding operations performed at a material removal rate of at least about 1.6 in.³/ min / in. [17.3 mm³/ s / mm] without evidence of damage (for example, burn) to the work piece. Other grinding parameters used in UHMRR grinding operations will be apparent based on the description.

The agglomerated abrasive bodies of the embodiments herein may have particular characteristics different from conventional high speed agglomerated abrasive articles. In particular, the abrasive articles agglomerated herein may have a particular combination of phases that facilitates improved performance, particularly in the field of UHMRR grinding operations.

References herein to grinding capabilities of the agglomerated abrasive body may relate to grinding operations, such as centerless grinding, cylindrical grinding, crankshaft grinding, various surface grinding operations, bearing and gear grinding operations, trailed feed grinding, and various tool shop grinding processes. In addition, work pieces suitable for grinding operations may include inorganic or organic materials. In particular cases, the workpiece may include a metal, metal alloy, plastic, or natural material. In one embodiment, the workpiece may include a ferrous metal, non-ferrous metal, metal alloy, metal superalloy, and a combination thereof. In another embodiment, the workpiece may include an organic material, including, for example, a polymeric material. In still other cases, the workpiece can be a natural material, including, for example, wood.

In particular cases, it has been pointed out that the agglomerated abrasive body is capable of grinding work pieces at ultra high material removal rates. For example, in one embodiment, the agglomerated abrasive body can perform a grinding operation at a material removal rate of at least about 1.60

I heard in. ³/ min / in. [17.3 mm³/ s / mm], such as 1.7 in. ³/min./in. [18.4

<td>mm³/ s / mm],</td><td>to the</td><td>less</td><td>approximately</td><td> 1.8</td><td>in. ³/ min / in.</td><td> [19.4</td>

<td>mm³/ s / mm],</td><td>to the</td><td>less</td><td>approximately</td><td> 1.9</td><td>in. ³/ min / in.</td><td> [20.5</td>

<td>mm³/ s / mm],</td><td>or</td><td colspan="2">even at least 2</td><td> . 0</td><td>in. ³/ min / in.</td><td> [21.6</td>

<td>mm / s / mm].</td><td>Yet,</td><td>the</td><td colspan="3">material removal rate</td><td>for</td>

certain agglomerated abrasive bodies may be no greater than approximately 5.0 in. ³/ min / in. [54 mm³/ s / mm], such as not more than about 4.5 in. ³/min./in. [48.6 mm³/ s / mm] during an ultra high speed material removal (UHMRR) grinding operation. It will be appreciated that the agglomerated abrasive bodies of the present application can grind a workpiece at material removal rates within a range between any of the minimum and maximum values ​​noted above.

It has been pointed out that the agglomerated abrasive body is capable of grinding work pieces at ultra high material removal rates and having limited wear. For example, in one embodiment, the agglomerated abrasive body may have a relative wear rate of no more than

<td colspan="3">approximately 90%,</td><td>in</td><td>where the</td><td>speed</td><td>from</td><td>wear</td>

<td>relative</td><td>I know</td><td>calculates</td><td>how</td><td>the change</td><td>on the radio</td><td>from</td><td>the wheel</td>

<td>after</td><td>from</td><td>perform</td><td>a</td><td>operation</td><td>grinding</td><td>from</td><td>UHMRR of</td>

<td>agreement</td><td>with</td><td colspan="2">a modality</td><td>In others</td><td>modalities,</td><td>the</td><td>speed</td>

relative wear of the agglomerated abrasive body may be less, such as not more than about 85%, no more than about 80%, no more than about 70%, no more than about 60%, or no more than about 4 0% during a grinding operation of UHMRR. Still, in a particular case, the abrasive bodies agglomerated herein can have a relative wear rate of at least about 5%, or even at least about 10% during a UHMRR grinding operation. It will be appreciated that the agglomerated abrasive bodies of the present application may have a wear rate within a range between any of the minimum and maximum percentages noted above.

Additionally, the agglomerated abrasive body may be able to grind work pieces at ultra high material removal rates and have a specific grinding energy. For example, in one embodiment, the agglomerated abrasive body may have a specific grinding energy, measured as the slope of a power curve against material removal rate, not greater than about 11 HP / in.³ min (30 J / mm³) during an ultra high speed grinding operation of material removal (UHMRR). In still other cases, the agglomerated abrasive articles of the embodiments herein may have a specific grinding energy not greater than about 10.9 HP / in.³ min (29.4 J / mm³), not greater than approximately 10.8 HP / in³ min (29.1 J / mm³), or even no greater than approximately 10.7 HP / in³ min (28.8 J / mm³) during an ultra high speed grinding operation of material removal (UHMRR). Still, according to one embodiment, the specific grinding energy can be at least about 5 HP / in.³ min (13.5 J / mm³), or even at least about 7 HP / in³ min (18.9 J / mm³) during an ultra high speed grinding operation of material removal (UHMRR). It will be appreciated that the agglomerated abrasive bodies of the present application may have a specific grinding energy during UHMRR grinding operations within a range between any of the minimum and maximum values ​​noted above.

In addition, the agglomerated abrasive body can be configured to perform ultra high speed grinding operations of material removal with improved efficiency. For example, in one embodiment, the agglomerated abrasive body may have a specific threshold power, which is a measure (or extrapolation) of the power used at a material removal rate of 0, based on the slope of a curve of the power plot versus material removal rate. According to one embodiment, the specific threshold power may be not greater than approximately (35.23J / s.mm) 1.2 Hp / in, such as not greater than approximately (32.29J / s.mm) 1.1 Hp / in, no greater than approximately (29.36J / s.mm) 1.0 HP / in, or even

0 7 not greater than approximately (26.42J / s.mm) 0.9 HP / in. Still, according to one modality, the specific threshold power can be at least approximately (2.94J / s.mm)

0.1 Hp / in, or even not greater than approximately (8.8 0 J / s.mm) 0.3

Hp / in.

It will be appreciated that the agglomerated abrasive bodies of the present application may have a specific threshold power within a range between any of the maximum minimum values ​​noted above.

During certain grinding operations, it has been pointed out that the agglomerated abrasive bodies of the present application can perform a grinding operation of

UHMRR at a particular average depth of cut (DOC).

For example, the depth of cut achieved by the agglomerated abrasive body can be at least about 0.003 inches (0.0762 mm). In other cases, the agglomerated abrasive body is capable of achieving a depth of cut during high speed grinding operations of at least about

0.007 inches (0.117 mm), such as at least about

0.01 inches (0.254 mm), or even at least approximately

0.015 inches (0.381 mm). Still, the average depth of cut for certain grinding operations of

UHMRR used by agglomerated abrasive bodies herein may not be greater than approximately 0.05 inches (1.27 mm), or not greater than approximately 0.03 inches (0.762 mm). It will be appreciated that the average depth of cut may be within a range between any of the minimum and maximum values ​​indicated above.

In other embodiments, it has been pointed out that the agglomerated abrasive body can grind a workpiece at a maximum power not exceeding approximately 10 Hp (7.5 kW) during UHMRR grinding operations. In other modalities, the maximum power during the operations of

<td colspan="2">high grinding</td><td colspan="2">speed can</td><td>Not to be</td><td>higher</td><td>what</td>

<td>approximately</td><td> 9</td><td>Hp</td><td colspan="2">(6.8 kW), as not</td><td>higher</td><td>what</td>

<td>approximately</td><td> 8</td><td>Hp</td><td>(6.0 kW), or</td><td>even not</td><td>higher</td><td>what</td>

<td>approximately</td><td> 7.5</td><td>Hp 1</td><td>5.6 kW).</td><td></td><td></td><td></td>

<td>The</td><td colspan="2">bodies</td><td>abrasive</td><td>agglomerates</td><td>from</td><td>the</td>

Modes herein can be used in a UHMRR grinding operation at a speed not exceeding 55 m / s. In other cases, the operating speed of the agglomerated abrasive body during a UHMRR grinding operation may be greater, such as not more than about 50 m / s, no greater than about 4 5 m / s, or no more than about 40 m / s In certain cases, the agglomerated abrasive body may be able to grind a workpiece in a UHMRR grinding operation at a speed of at least about 5 m / s, such as at least about 10 m / s, at least about 2 0 m / s, or even at least about 3 0 m / s. It will be appreciated that the agglomerated abrasive bodies of the embodiments herein can perform a UHMRR grinding operation on a workpiece at a speed within a range between any of the minimum and maximum values ​​noted above.

The agglomerated abrasive bodies of the embodiments herein can be configured to perform a UHMRR grinding operation that has a G ratio, which is a measure of the material removed from the workpiece divided by the volume of material lost from the workpiece. working, of at least about 0.1, such as at least about 0.13, at least about 0.16, or even at least about 0.2.

The reference herein to grinding capabilities of the agglomerated abrasive body may relate to grinding operations, such as centerless grinding, cylindrical grinding, crankshaft grinding, various surface grinding operations, bearing and gear grinding operations, trailed feed grinding, and various tool shop grinding processes. In addition, work pieces suitable for grinding operations may include inorganic or organic materials. In particular cases, the workpiece may include a metal, metal alloy, plastic, or natural material. In one embodiment, the workpiece may include a ferrous metal, non-ferrous metal, metal alloy, metal superalloy, and a combination thereof. In another embodiment, the workpiece may include an organic material, including, for example, a polymeric material. In still other cases, the workpiece can be a natural material, including, for example, wood.

It will be appreciated that various types of non-agglomerated abrasive particles can be used in the present embodiments. For example, the agglomerated abrasive body may include a non-agglomerated abrasive particle that includes an abrasive material that includes a carbide, an oxide, a nitride, a boride, an oxycarbon, an oxynitride, and a combination thereof. In a particular case, the agglomerated abrasive body may include non-agglomerated abrasive particles including silicon carbide. The non-agglomerated abrasive particles can be a superabrasive material, such as cubic boron nitride or diamond.

According to another embodiment, the non-agglomerated abrasive particles can be shaped abrasive particles. Shaped abrasive particles can have a well-defined and regular (i.e., non-random) arrangement of the edges and sides, thereby defining an identifiable shape. For example, a shaped abrasive particle can have a polygonal shape as seen in a plane defined by any of two dimensions of length, width, and height. Some exemplary polygonal shapes can be triangular, quadrilateral (for example, rectangular, square, trapezoidal, parallelogram), a pentagon, a hexagon, a heptagon, an octagon, a nonagon, a decagon, and the like. Additionally, the shaped abrasive particle may have a three-dimensional shape defined by a polyhedral shape, such as a prismatic shape or the like. In addition, the shaped abrasive particles may have curved edges and / or surfaces, such that the shaped abrasive particles may have convex, concave, ellipsoidal shapes.

The shaped abrasive particles may be in the form of any alphanumeric character, for example, 1, 2, 3, etc., A, B, C, etc. In addition, the shaped abrasive particles may be in the form of a character selected from the Greek alphabet, the modern Latin alphabet, the ancient Latin alphabet, the Russian alphabet, any other alphabet (e.g. Kanji characters), and any combination thereof. .

The shaped abrasive particle can have a body that defines a length (1), a height (h), and a width (w), where the length is greater than or equal to the height, and the height is greater than or equal to the width

In addition, in a particular aspect, the body may include a primary aspect ratio defined by the length: height ratio of at least about 1: 1. The body can also include a vertical orientation probability of at least about 50%. In another aspect, the shaped abrasive particle may have a body having a length (1), a width (w), and a height (h), where the length, width, and height may correspond to a longitudinal axis, a lateral axis, and a vertical axis, respectively, and the longitudinal axis, lateral axis, and vertical axis can define three perpendicular planes. In this aspect, the body can include an asymmetric geometry with respect to any of the three perpendicular planes.

In yet another aspect, the shaped abrasive particle may include a body that has a complex three-dimensional geometry that includes 3-fold symmetry in three perpendicular planes defined by a longitudinal axis, a lateral axis, and a vertical axis. In addition, the body may include an opening that extends through the entire interior of the body along one of the longitudinal axis, lateral axis, or vertical axis.

In yet another aspect, the shaped abrasive particle can include a body having a complex three-dimensional geometry defined by a length (1), a width (w), and a height (h). The body can also include a center of mass and a geometric midpoint. The center of mass can be displaced from the geometric midpoint by a distance (Dh) of at least about 0.05 (h) along a vertical axis of the body that defines the height.

In another aspect, the shaped abrasive particle may include a body that defines a length (1), a width (w), and a height (h). The body may include a base surface and an upper surface. In addition, the base surface comprises a different cross-sectional shape of a cross-sectional shape of the upper surface.

In yet another aspect, the shaped abrasive particle can include a body that has a generally flat bottom part and a dome shape that extends from the generally flat bottom part.

In another aspect, the shaped abrasive particle may include a body that defines a length (1), a width (w), and a height (h). The length, width, and height may correspond to a longitudinal axis, a lateral axis, and a vertical axis, respectively. In addition, the body may include a rotation along a longitudinal axis that defines the length of the body such that a base surface is rotated with respect to an upper surface to establish a rotation angle.

In still another aspect, the shaped abrasive particle may include a body having a first end face and a second end face, at least three adjacent side faces extending between the first end face and the second end face, and an edge structure established between each pair of adjacent side faces.

In another aspect, the shaped abrasive particle may include a body that has a central portion and at least three radial arms extending outwardly from the central portion along the entire length of the central portion.

Examples

Example 1

Four samples of agglomerated abrasive bodies were obtained. Sample SI was formed in accordance with the modalities herein, which has porosity of about 52% by volume to about 58% by volume, a content of abrasive particulate material within a range between 34% by volume and 40% by volume including a content of abrasive agglomerates between 34% by volume and 40% by volume and a content of non-agglomerated abrasive particles of microcrystalline alumina between about 0 % by volume and approximately 5% by volume. Abrasive agglomerates contain approximately

70% by volume to 90% by volume of alumina abrasive particles, 1% by volume to 4% by volume binder, and the rest is porosity. The vitreous binder composition of the abrasive agglomerates is provided in Table 1 below. The agglomerated abrasive body of Sample SI has a content of vitreous binder material between about 3% by volume to 8% by volume. The composition of the binder material is provided in Table 2 below. The SI Sample also includes an alumina bubble content within a range between about 4% by volume to 6% by volume.

Sample SI was formed from a mixture that was initially cold pressed to form wheels and cooked at a temperature of approximately 900 ° C to 1250 ° C having a vitreous binder material.

Table 1 - Composition of Abrasive Agglomerate Vitreous Binder

Oxide S1O2 AI2O3 Fe₂OR₃ Uncle₃ CaO Na₂0 K₂0 Li₂0 B₂OR₃ Weight% 52-58 12-14 &lt;1 &lt;1 &lt;1 7.5-10 &lt;1 2-3 12-18

Table 2 - Composition of Vitreous Abrasive Wheel Agglomerate

<td>SiO₂</td><td> 48-52</td>

<td>A1₂OR₃</td><td> 15-20</td>

<td>Faith₂OR₃</td><td>Traces (&lt;1.0%)</td>

<td>Uncle₂</td><td>Traces</td>

<td>CaO</td><td> 1-1.5</td>

<td>MgO</td><td>Traces</td>

<td>L12O</td><td> 2-5</td>

<td>Na₂0</td><td> 5-10</td>

<td>K₂0</td><td> 2-5</td>

<td>B₂OR₂</td><td> 10-17</td>

Two conventional CS1 and CS2 samples were obtained from Saint-Gobain Abrasives, Inc. and are commercially available as Vortex Bonded Abrasive Wheels Structures D28, D29, respectively]. Samples CS1 and CS2 have the same structure as Sample SI, including approximately 52% by volume to 58% by volume of porosity, an abrasive agglomerate content between 34% in. volume and 4.0% by volume, and a vitreous binder content of between about 3% by volume to 8% by volume. Abrasive agglomerates contain approximately 7 0% by volume to 90% by volume of alumina abrasive particles, 1% by volume to 4% by volume binder, and the rest is porosity. The vitreous binder composition of the abrasive agglomerates is provided in Table 3 below. The composition of the binder material is provided in Table 4 below. Samples CS1 and CS2 have no alumina bubble material or non-agglomerated abrasive particles.

Table 3: Composition of Sample CS2 of Agglomerate Binder

<td>Oxide</td><td>SiO₂</td><td>To the₂0₃</td><td>Faith₂OR₃</td><td>Uncle₂</td>

<td>% in weigh</td><td> 52-58</td><td> 12-14</td><td> &lt;1</td><td> &lt;1</td>

<td>CS2</td><td>Table</td><td> 4 :</td><td colspan="2">Composition</td>

<td>Oxide</td><td>SiO₂</td><td>A1₂OR₃</td><td>F Θ2Ο3</td><td>Uncle₂</td>

<td>% in weigh</td><td> 52-58</td><td> 12-14</td><td> &lt;1</td><td> &lt;1</td>

<td>CaO</td><td>Na₂0</td><td>K₂OR</td><td>Li₂OR</td><td>B₂OR₃</td>

<td> &lt;1</td><td> 7.5-10</td><td> &lt;1</td><td> 2-3</td><td> 12-18</td>

<td colspan="3">of Binder of</td><td>the</td><td>Shows</td>

<td>CaO</td><td>Na₂0</td><td>K₂OR</td><td>Li₂OR</td><td>b₂or₃</td>

<td> &lt;1</td><td> 7.5-10</td><td> &lt;1</td><td> 2-3</td><td> 12-18</td>

Each sample is used in a UHMRR drag feed grinding test according to the following parameters. The table speed varied between 100, 300, 500, 700, 900, 1200, 1600, 2000, 2400, 2800, 3200 and 3600 mm / min. The average cutting depth was 0.5 mm, and for a fixed cutting depth, the table speed was progressively increased. The width of the grooves formed is set at 10 mm. The material removal rate was varied between 0.83 to 30 mm³/ s / mm in an Inconel work piece. The wheel speed was approximately 35 m / s. A 3% emulsion refrigerant (Oel-Held) was also used.

The abrasive bodies were re-sharpened according to the following conditions.

Refining Conditions:

Type: Rotary Sharpener

Roller Description:

Norton RPC 1312-2 # 11

Refining Configuration:

Non-continuous re-sharpening

Diameter (in):

Comp. Re-sharpening (μίη / step): 20.0

Sharpener Speed ​​Ratio: 0.8

FIG. 1 includes a graph of average power (kW) versus material removal rate (mm³/ s / mm). As illustrated, the power extracted by each of the samples (SI, CS1, and CS2) is relatively the same.

FIG. 2 is a graph of ratio G (volume of material removed / volume of wheel wear) versus material removal speed (mm³/ s / mm). Notably, at high material removal rates, particularly those exceeding 20 mm³/ s / mm, the SI Sample demonstrates an improved G ratio compared to conventional samples. In fact, for example, at a material removal rate of approximately 23 mm³/ s / mm, Samples CS1 and CS2 have a G ratio of approximately 0.1, while Sample SI has a G ratio of approximately 0.28, respectively. The percentage difference in the G ratio between the SI Sample and the conventional Samples CS1 and CS2 is above a 100% difference. The SI Sample has a G ratio that is at least 2 times better, and almost 3 times better than conventional samples (CS1 and CS2) at high material removal rates.

FIG. 3 is a graph of radial wheel wear (Ars in mm) against material removal speed (mm³/ s / mm). Notably, at high material removal rates, particularly those exceeding 20 mm³/ s / mm, the SI Sample shows remarkably very limited wheel wear compared to the state of the art CS1 and CS2 wheels. Notably, as illustrated, at a material removal rate of approximately 23 mm³/ s / mm, Samples CS1 and CS2 have a wear of almost three times the wear of the SI Sample. At a material removal rate of approximately 27 mm³/ s / mm, Samples CS1 and CS2 have a wear of almost three times the wear of the SI Sample. And, at a material removal rate of approximately 30 mm³/ s / mm, Samples CS1 and CS2 have a wear rate of almost triple the wear of the SI Sample. The SI Sample demonstrates limited wear at ultra high material removal rates compared to conventional samples (CS1 and CS2).

FIG. 4 is a graph of the edge radius (mm) against the material removal rate (mm³/ s / mm). The edge radius is a measure of the rounding of the edge of the grinding wheel, which is measured via optical comparator. Notably, at high material removal rates, particularly those exceeding 20 mm³/ s / mm, Sample SI demonstrates unexpectedly low corner rounding (under edge radius) compared to wheels CS1 and CS2. Notably, as illustrated in FIG. 4, at a material removal rate of approximately 23 mm³/ s / mm The

<td>Samples</td><td>CS1</td><td colspan="2">and CS2 have</td><td colspan="2">an edge radius almost twice</td><td>the</td>

<td>radio of</td><td>the</td><td>Shows</td><td>YES</td><td>In addition, to older</td><td>speeds</td><td>from</td>

<td>removal</td><td>from</td><td>material</td><td>from</td><td>approximately 27</td><td>mm³ / s / mm and</td><td> 30</td>

<td>mm³/ s / mm,</td><td>the</td><td>smoothed</td><td>from</td><td>the corners of the</td><td>CS1 samples</td><td>Y</td>

CS2 increases dramatically, while the rounding of the corners of the SI Sample is limited, and in all cases, it is less than half of the measured radius of Samples CS1 and CS2. The SI Sample demonstrates an improved corner sustained at ultra high material removal rates compared to conventional samples (CS1 and CS2).

FIGs. 5 and 6 are illustrations of the loss of form between a conventional sample representative of Sample CS1 or CS2 and a sample according to the modalities herein, representative of Sample SI. As clearly illustrated, after performing a UHMRR grinding process according to the conditions as in the previous example, the representative sample of the modalities herein (SI) has limited wear (See, FIG. 6). However, the conventional sample, which is illustrated in FIG. 5, is significantly torn off and demonstrates significant loss of form.

FIG. 7 includes a graph of the actual material removal rate versus theoretical removal rate for Samples SI, CS1, and CS2. As illustrated, Sample SI demonstrates a real material removal rate significantly above the actual material removal rate capabilities of conventional samples CS1 and CS2.

FIG. 8 includes a graph of the surface roughness (Ra) against the material removal rate for each of the samples. As illustrated, Sample SI demonstrated equal or better capacity for grinding the workpiece at a suitable surface roughness compared to conventional samples CS1 and CS2.

Example 2

Additional comparative grinding studies were carried out to compare the high-speed grinding capabilities of material removal of the agglomerated abrasive articles of the embodiments herein for conventional grinding abrasive articles.

Five samples of agglomerated abrasive bodies were obtained. Samples S3, S4, and S5 were formed according to the modalities herein and have the structure of Sample SI of Example 1 above.

Two conventional CS3 and CS4 Samples were obtained from Saint-Gobain Abrasives, Inc. Sample CS3 is commercially available as a Vortex Bonded Abrasive Wheel and is the same as Sample CS1 in Example 1.

The CS4 Sample is commercially available as Quantum Creepfeed Product that has a structure of approximately 40% by volume to 50% by volume of porosity, a content of microcrystalline alumina abrasive particles between 3% by volume and 15% by volume, and a content of vitreous binder between about 4% by volume to 7% by volume. The composition of the binder material is provided in Table 5 below. Sample CS4 has 1-5% by volume of alumina bubble material and non-abrasive agglomerates.

<td colspan="2">Table 5:</td><td colspan="2">Composition</td><td>from</td><td>Binder of the</td><td>Shows</td>

<td>conventional</td><td>CS4</td><td></td><td></td><td></td><td></td><td></td>

<td>SiOs AI2O3</td><td>FS2O3</td><td>Uncle₂</td><td>CaO</td><td>MgO</td><td>Na₂okay₂0 Li₂OR</td><td>B2O3</td>

<td> 50-</td><td></td><td></td><td></td><td></td><td></td><td></td>

<td> 10-17</td><td> &lt;1</td><td> &lt;1</td><td> &lt;1</td><td> &lt;1</td><td> '5-10 1-12 1-5</td><td> 10-15</td>

Each sample was analyzed according to a similar UHMRR grinding test condition as detailed above in Example 1.

FIG. 9 is a diagram of the maximum material removal rate (in³/ min / in) for each of the samples before the workpiece exhibits burn. As illustrated, CS4 and CS3 demonstrate significantly lower material removal rates before damaging the workpiece. In fact, Sample S3 demonstrates a 10% improvement in the maximum material removal rate over Sample CS3 and better than a 20% improvement in maximum material removal rate compared to Sample CS4. In addition, Sample S4 demonstrates almost a 20% improvement in the maximum material removal rate over Sample CS3 and better than a 35% improvement in the maximum material removal rate compared to Sample CS4. Sample S5 demonstrates an improvement in the maximum material removal rate greater than 30% over Sample CS3 and better than a 40% improvement in maximum material removal rate compared to Sample CS4. Samples S3-S5 demonstrate improved operation at ultra high material removal rates compared to conventional samples (CS3 and CS4).

FIG. 10 includes a graph of average unit power (Hp / in) against material removal rate (in³/ min / in) for each of the samples. As clearly illustrated, Samples S3, S4, and S5 demonstrate a lower power extracted at each of the material removal rates compared to Samples CS3 and CS4. In addition, Samples S3-S5 have a lower specific grinding energy, which is a measure of the slope of the respective graph lines, as compared to Samples CS3 and CS4. In addition, as evidenced again, Samples S3-S5 were able to grind at higher material removal rates before ceasing the grinding operation compared to CS3 and CS4.

<td>Machine:</td><td>Blohm</td><td>Material:</td><td> 4340.000</td>

<td>Type of refrigerant:</td><td>E812</td><td>Hardness:</td><td>4 0 RC</td>

<td>Wheel Speed ​​[sfpm]:</td><td> 5000</td><td></td><td></td>

<td>Table Speed ​​[ipm]:</td><td>Var.</td><td></td><td></td>

<td>Sharpening Tool:</td><td>Roller Dia.</td><td></td><td></td>

<td>Sharpener Speed ​​Ratio:</td><td> 0.8</td><td></td><td></td>

<td>Comp. Sharpening [in / rev]:</td><td> 40.000000</td><td></td><td></td>

<td>Sharpening Speed</td><td></td><td></td><td></td>

<td>[in / min]:</td><td></td><td></td><td></td>

<td>Premolated:</td><td> 0.0100</td><td></td><td></td>

The above modalities are directed to abrasive products, and particularly agglomerated abrasive products, which represent a deviation from the state of the art. Agglomerated abrasive products of the embodiments herein use a combination of features that facilitate improved grinding performance. As described in the present application, the agglomerated abrasive bodies of the embodiments herein use a combination of non-limiting characteristics including a particular amount and type of particular abrasive material, including non-agglomerated abrasive and abrasive agglomerates, particular amount and type of material. binder, type of binder material, type of agglomerates that have certain materials and characteristics, certain pore formers, and a particular amount of porosity. In addition to the discovery that such products could be formed effectively, despite being outside the known scope of conventional abrasive products in terms of their grade and structure, it was also discovered that such products demonstrated improved grinding performance. Notably, it was discovered that the agglomerated abrasives of the present embodiments are capable of performing efficient grinding operations at the ultra high material removal rates. In fact, quite surprisingly, the agglomerated abrasive bodies of the embodiments herein demonstrated an ability to grind at ultra high material removal rates, while also demonstrating improved wear, grinding energy, and adequate surface finish compared to wheels. of high speed grinding of the state of the art.

In the above, the reference to specific modalities and the connections of certain components is illustrative. It will be appreciated that the reference to the components being coupled or connected is intended to describe either direct connection between the components or indirect connection through one or more intervening components as will be appreciated to perform the methods as discussed herein. As such, the subject described above is considered illustrative, and not restrictive, and the appended claims are intended to cover all of these modifications, improvements, and other modalities, which fall within the true scope of the present invention. Therefore, to the maximum extent permitted by law, the scope of the present invention will be determined by the broadest permitted interpretation of the following claims and their equivalents, and should not be restricted or limited by the above detailed description.

The summary of the description is provided to comply with the Patent Law and is presented in the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the Detailed Description above, various features can be grouped together or described in a single mode for the purpose of streamlining the description. This description will not be interpreted as reflecting an intention that the claimed modalities require more features that are expressly cited in each claim. Rather, as the following claims reflect, the subject of the invention can be directed to less than all the characteristics of any of

<td>the modalities</td><td>described. By</td><td>the</td><td>Both</td><td>following</td>

<td>claims</td><td>are incorporated into</td><td>the</td><td>Description</td><td>Detailed,</td>

<td colspan="2">with each claim placed</td><td>yes</td><td>same as</td><td>defining</td>

<td>separately the</td><td>subject rec1amado.</td><td></td><td></td><td></td>

<td>It does</td><td>record that with</td><td>I laughed</td><td>ation to this</td><td>date on</td>

The best method known by the applicant to implement said invention is that which is clear from the present description of the invention.