PRODUCTION OF POWDER FOR PRODUCING COMPACT OF ANISOTROPIC SINTERED HARD ALLOY OR COMPACT USING SAME

摘要

PURPOSE:To produce a sintered hard alloy compact having superior crack propagation resistance and toughness as cutting tool and wear resistant parts and also having high proportion of anisotropic crystals by regulating the grain size of WC and. the amount of Co as raw materials at the time of producing a WC-Co sintered hard alloy. CONSTITUTION:A sintered hard alloy, after sintering, having a composition consisting of 5 to 15wt.% Co and the balance WC of 0.8 to 2.5mum average grain size is heated and oxidized in the air, heated in a hydrogen air flow to undergo reduction, and further carbonized in a hydrogen air flow with the addition of carbon, by which a powder of WC-Co sintered hard alloy having high proportion of anisotropic crystals is produced. This powder is press- compacted independently or with the addition to respective powders of Co and WC and sintered or subjected to hot pressing, by which the sintered compact of the WC-Co sintered hard alloy excellent in crack propagation resistance and toughness can be produced in high yield.