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Powder metallurgy produced tools with variously combined cutting and supporting parts In high speed steel tools are often used for the purpose of saving alloying elements unalloyed steel beams, which receive an armor by welding of high-speed steel or by soldering shaped high-speed steel plates. When welding, there is the disadvantage that the weld bead must be made of high-speed steel by grinding and in the final shape, thereby labor and material losses occur while the compound produced by soldering grown no heavy use.

It has already been described a method for the production of tools with attached or inserted hard metal parts, in which the simultaneous production of the actual carrier and the associated hard metal part takes place on a sintered metallurgical way. This known method consists for. B. in that one presses a metal in powder form in a shape corresponding to the article to be produced, then inserting a metal foil or a metal fabric to prevent mixing and then the metal of the other part in powder form fills and fertigpreßt. In cases where mixing of the two powder types is not to be feared, the insertion of the metal separating foil can also be omitted.

Furthermore, the production of sintered metallic bodies is known, which consist of at least two different sintered components in which a hard-to-iron iron, such as tungsten, molybdenum, etc., and / or hard materials, such as carbides, nitrides, silicides Boride, and in which the proportions of refractory metal or hard material in at least one direction change continuously.

Such bodies may have a work surface of very high hardness for metalworking. The preparation is made of a mixture of carbides u. Like., Where the contents of admixed auxiliary metal, z. Cobalt, nickel and iron, increase more or less continuously in the direction away from the working surface.

Finally, a method for the production of composite metals has become known in which the individual layers of the corresponding metal powders are pressed and sintered together. By a subsequent heat treatment, a partial or complete homogenization can be achieved.

Despite the excellent hardness of the hard alloys, the high-speed steels have been able to hold their own in various fields, such as drilling, milling, sawing, broaching and tapping. When drilling tough metals z. B. when removing the chip from the well, the brittle hard metals easily injured. The invention takes these circumstances into account and consists in producing tools, in particular smaller drills, milling cutters, etc., with differently shaped cutting and supporting parts by powder metallurgy such that high-speed steel powder for the cutting part and carbon steel powder for the supporting part induce a passing transition sintered together between the two types of powder.

The high-speed steel composite tools according to the invention, which have a cutting part consisting of high-speed steel and a passing transition to the support part material, avoid the disadvantages of the tools produced by brazing the cutting edge on the support made of carbon steel.