Abstract: Tools for machining etc can according to the invention be made better and cheaper by being composed of a compound material forming core and cover resp of the tool. The core consists thereby of a material which is situated in the gap between cemented carbide and high speed steel regarding its properties and which contains 30-70 vol % hard constituents in the form of carbides, nitrides and/or carbonitrides of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and/or W in a matrix based on Fe, Ni, and/or Co and that the cover comprises an alloy based on Fe, Co and/or Ni generally steel and preferably tool steel or stainless steel.

Abstract: A method of producing coolant channels in a metallic object such as a cutting tool whereby a blank is formed by at least one working step such as compaction etc. and the channels are formed by cores whereby the working takes place as a compaction at a temperature of at least 950.degree. C. and that the core thereafter is removed in a separate step.

Abstract: Wear parts or cutting tools, in which the part being exposed to wear is essentially an extremely difficultly grindable material (e.g., hard material), but in which the manufacture of the wear part or cutting tool requires considerable grinding operations can, according to the invention, be made better and cheaper forming the wear part or cutting tool of a compound material which is a wear-resistant (or difficult to grind) surface and a supporting surface of high speed steel or tool steel.