METHOD FOR PRODUCING POWDER METAL COMPOSITIONS FOR WEAR AND TEMPERATURE RESISTANCE APPLICATIONS AND METHOD OF PRODUCING SAME

摘要

A powder metal composition for high wear and temperature applications is made by atomizing a melted iron based alloy including 3.0 to 7.0 wt. % carbon; 10.0 to 25.0 wt. % chromium; 1.0 to 5.0 wt. % tungsten; 3.5 to 7.0 wt. % vanadium; 1.0 to 5.0 wt. % molybdenum; not greater than 0.5 wt. % oxygen; and at least 40.0 wt. % iron. The high carbon content reduces the solubility of oxygen in the melt and thus lowers the oxygen content to a level below which would cause the carbide-forming elements to oxidize during atomization. The powder metal composition includes metal carbides in an amount of at least 15 vol. %. The microhardness of the powder metal composition increases with increasing amounts of carbon and is typically about 800 to 1,500 Hv50.