Sintered hard alloy and its manufacture

Abstract

Abstract PURPOSE: To obtain a hard alloy having superior wear resistance, mechanical toughness and heat crack resistance by mixing WC crystal powder, BI-type crystal powder and Fe group metal powder and sintering the mixed powder in a specified nitrogen atmosphere to prevent denitrification. CONSTITUTION: WC crystal powder, BI-type crystal powder having an Nb to (Ta+Nb) molar ratio of ≥0.5 and an N to (C+N) molar ratio of 0.1W0.5 and Fe group metal powder are mixed and sintered in a 10 -2 W10 -4 Torr vacuum or sintered while holding the partial pressure of nitrogen intermittently or continuously at 0.1W500Torr in temp. raising, holding and cooling processes. Thus, a uniform alloy is obtd. while preventing denitrification or enriching nitrogen. This alloy is suitable for use as a base material for a covered carbide tool, etc. COPYRIGHT: (C)1981,JPO&Japio

Inventors

• 👤 Kunihiro Takahashi
• 👤 Akio Hara

Bibliographic Details