Method for the production of metallic formed members

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Patent Office (62) National application number (86) International filing date (86) Filing date for European patent application (30) Pnettetsinformation (11) Publication86-11-17 ^number 447455

80-06-07

7g_i1-29

Application received as

79-11-29

H Swedish patent application □ Completed international patent application with number □ converted European patent application with number

78-12-06 OE 2852657 (71) Applicant Diehl GmbH & Co, NCirnberg DE (72) Inventor S. Rhau, A. Weber, NOrnberg, Neunkirchen (74) Representative Sydsvenska patentbyrån AB (54) Designation procedure for the production of a splitter grenades intended for splitter body (56) Published publications: DE 2,129,196 (F42B: 13/18), US 3,281,921 (29-573) Other publications: Zeitschrift fur Metallkunde, Bd. 58 (1967), H. 7

E. Gross et al., Uber das Plattieren von Stahl and Zircaloy-2 in tubes by round hammers, pages 487-490 (57) Summary:

A splitter body with metallic bed masses stored in metallic bed mass is expensive to produce by sintering. Cold round smiths, on the other hand, are more economical. In addition, a significant increase in splitter energy is obtained upon detonation of the splitter body. In a cavity between a main body (3) and an outer casing (10), the balls (12) are arranged before the machining begins. The machining of the outer casing presses the main body material and outer casing material between the ball cavity, densifies the main body and the outer casing, and biases the outer casing and the beads. As a result, the inner casing formed by the main body can be very thin. The bias of the balls and outer casing together with the thin inner casing gives high energy to the casing split and the balls.

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The present invention relates to a process for producing a splitter body for splitter grenades according to the preamble of claim 1.

By DE Patent Specification 2,460,013, a process for the production of splitter bodies with metallic bedding stored in separate parts is previously edge. The parts are secured in a metallic holder and surrounded by a bed of metal powder. The holder with parts and bed mass is isostatically pressed and sintered. The splitter bodies thus obtained for projectiles show good splitting effect. However, the production of the splitter sheath is costly, since after sintering several millimeters of irregularity often occur in the outer sheath which must be removed by a machining process. Thus, in order to maintain the intended caliber size, the original outer diameter of the splitter cover must be selected relatively large in order to eliminate such errors. The machining portion of the splitter housing is thus relatively large. In addition, the splitter effect is not reproducible in each case, since in the pressing process the bed mass penetrates variously deep into the spaces between the parts.

Another disadvantage is that the sintering process can reduce the use of the metallurgical properties of the materials, such as hardness, toughness,

447 455 etc. The said heating process also limits the number of substances that may be relevant for the individual parts.

DE Patent Specification 2,129,196 also discloses a splitter body for splitter grenades. Between two arranged tubular bodies, ball-shaped splitter is stored. Through high pressure deformation, the inner tube body is pressed into the space between the splits. Thus, the tube bodies are pre-fragmented and plated together with the split into a splitter housing. High pressure deformation can occur in a shocking manner, e.g. by explosion or electromagnetic or by sealing by means of a calibration bolt.

Such deformation has the disadvantage that, due to the deformation rate within the excessive bandwidth, the splitter action is not reproducible to the extent required, resulting in the very high specific surface pressure distributed on the splitter housing, which breaks the beads of e.g. hardened steel such as ball bearing steel, and that the deformerina of the inner casing material exceeds the tensile limits thereof, with a non-predictable decrease in strength. This decrease also affects the splitting effect.

The present invention is intended to provide a SD grit body for splendid grenades which are economical to manufacture and exhibit reproducible splitter action. This is accomplished by means of the features set forth in the characterizing part of claim 1.

By the invention it is advantageously achieved that by the deformation of the outer casing, stresses are created therein which together with the compressive stress of the balls constitute a substantial increase in the splitter energy at the parts and the outer casing split, that the inner casing can be very thin so that when detonating the embedded explosive casing the highest possible amount of energy is passed through the fragmented inner housing to the parts. The deformation force exerted on the outside causes the outer casing and the parts in the form of balls to be deformed to the inner casing.

This results in a cold anchorage in the area of ​​the bullets deformed by the balls. The parts are thereby formed into the main body in a radial direction and in the regions therefor provide zones of greater hardness and thus greater strength between which narrow zones lie down less strength. The zones of lesser strength determine the fragmentation. For this fragmentation, less energy is required than for an inner sleeve of correspondingly high strength.

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Furthermore, it is achieved that the voids between the main body and the wetting sheath and the parts are as small as possible, whereby large mass, namely special mass with high density, is available as an energy carrier.

In addition, through the deformation, it is achieved that splitter corpses of high maturity and excellent shape are obtained ie. that the machining part is relatively small and the static and dynamic imbalances, which are crucial for high accuracy, are relatively small.

The inventions result in the separate parts being reproducibly pressed against each other and bounded in the elastic region or deformed in the elastic and inelastic regions. Thus, the parts essential for fragmentation of the outer envelope transmit the detonation energy completely in the region of the parts' storage in the outer envelope, when there is a zonal strength gain in the inner envelope.

The invention furthermore causes the material of the outer and inner envelopes in relation to the caliber of the splitter body to enclose the parts to 70% of the surface thereof, and upon detonation, the parts hit with relatively little specific surface pressure so that they are not destroyed.

The invention allows all parts of the splitter body to be deformed cold, for which several substances, including compounds, are suitable.

Furthermore, the cold deformation permits that no changes to the hardness of the separate parts, since no thermal load is present.

Finally, Surprisingly achieved, despite the cold deformation of the seoarate parts of hardened steel, heavy metal or enriched uranium, a spacer is not necessarily required, because through the 70% embedding of the beads into the inner and outer casing materials, the parts are broken through non-plastic deformers. .

In parts of cemented carbide, however, a spacer grille is necessary, since it is not plastic deformable.

The distance grid is absolutely necessary for cemented carbide bullets as cemented carbide is not deformable. Hereby, the spacer allows embedding of the beads in the material to these surrounding parts without destroying the cemented carbide beads.

For the deformable beads of thin metal, hardened steel or enriched steel within certain limits, it is possible to achieve a better embedding with spacers than without. The balls are only pressed after an "ice's degree of embeddedness toward each other. Thus, after mutual contact, it is possible to further deform the splitter body to further increase the degree of embedding.

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The invention will be described in more detail below with reference to the accompanying drawing, in which Figure 1 shows a starting body splitter body with a main body, Figure 2 shows a part of a circular forging machine with a splitter body and an inner housing, Figure 3 is a section along line III-III in FIG. Figure 2, Figure 4 shows a section IV of Figure 2 in magnification without forging jaws and mandrel, respectively, and Figure 5 shows section IV in the finished state.

In the drawings, 1 denotes a device for round forging, 2 a splitter body, 3 a main body, 4 a rotating clamp head, 5 a mandrel holder, 6 a distance, 7 a mandrel, 8 forging jaws, 10 an outer casing of steel C 45, 11 an inner casing of steel C 45, 12 hardened balls of ball bearing steel 100 Crö, 13 and 14 traction zones, 15 an incision, 18 heels, 19 a forging sweat, 20 diameter in finished state, 21 a diameter, 22 a distance grid, 22 'stec, 23 a distance , 24 an inner side, 25 an original split circle, 27 a split circle in the finished state.

The inner sheath 11 is clamped in the clamping head 4 of the circular forging device 1 only mentioned. The sheath has for the balls 12 a cut-off defined by heels 18. The balls 12 and the outer and inner shells 10, 11 are supported radially by the fixed or movable mandrel 7.

The forging jaws 8 have a concave forging surface 19 with a given radius approximately equal to the diameter of the outer casing 10 in finished condition (Figure 5). In the axial direction of the splitter bodies 2, the forging jaws are slightly longer than the notch 15 and cover the same throughout its length.

The diameter 21 of the main bodies 3 and the inner casing 11 corresponds to the diameter 20 in finished condition. 21 'is the diameter of the original state.

If instead of the inner sheath 11 of Figure 2, the main body 3 of Figure 1 is used, this is fixed to the clamp head 4. On the opposite side, a mandrel or end holder (not shown) engages the main body 3.

After the outer casing 10 has been slid over the spheres 22 in a spacer 22 with compressible steps 22, spaced at a distance 23 and mounted in the device 1, the forging process begins. Therein, for example, the forging jaws 8 simultaneously push against the rotatably driven splitter body. 2 in accordance with Figure 1 or 2. First, the distance 6 becomes equal to zero when the inside 24 of the outer casing 10 is pressed against the balls 12.

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Then the balls in the casings 10 and 11 and in the casing 10 and the main body 3 are gradually increased until, according to Figure 5, the final state is reached. The distance 23 becomes zero as the original partition circle 25 at the forging becomes the smaller, finished partition circle 27. The balls 12 are pressed against each other, a compressive tension arises under the balls, and the material of the steps 22 'is pushed aside.

The main body 3 and the inner casing 11, which is unobstructed by the mandrel 7, respectively, have the information of the bullets, zones 13 of higher strength and zones 14 of lower strength. So does the outer casing 10. In addition, the outer casing 10 exhibits tensile stresses generated by the deformation of the balls in the elastic or elastic and plastic region. The balls 12 are printed during forging and take up part of the deformation work (compressive stress). After the forging. the balls 12 transfer part of the deformation work on the outer casing 10 and a smaller part on their support (inner casing 11 and main body 3, respectively). This deformation work taken from said parts results in these correspondingly large tensile stresses. The tensile stresses are greater in the outer casing 10 than in the inner casing.

After forging, the splitter body 2 is in some cases still easy to rotate and requires the main body 3 to be further machined to provide an inner casing 11 corresponding to the sleeve of Figure 2. Thereafter, machining procedures are performed to provide the splitter body with the projectile parts provided thereon.