POWDER METALLURGY HIGH-SPEED STEEL FOR LARGE-SIZED COMPLEX TOOL AND PREPARATION METHOD THEREFOR

摘要

A powder metallurgy high-speed steel for a large-sized complex tool and a preparation method therefor. The preparation method comprises the following steps: preparing a powder mixture; sieving; cold pressing into billets; sintering; hot forging; heat treatment; and hardness test. The method has the following beneficial effects: the powder metallurgy high-speed steel of high performance is prepared by combining the grinding process, cold press molding and electromagnetic heating high-temperature sintering technology, the process of smelting raw metal is omitted, the processing efficiency is improved, the cost is saved, an interface between metal carbide and iron powder and cobalt powder particles is purified by inflating inert gases into an electromagnetic heating high-temperature sintering device and conducting a carbon-oxygen reaction on free carbon in the metal carbide and oxygen on the interface of iron powder and cobalt powder particles, and meanwhile forging and corresponding heat treatment are carried out, thereby improving the strength and toughness of the powder high-speed steel.