MIXING METHOD FOR RAW POWDER FOR POWDER METALLURGY AND PROCESS FOR PRODUCING RAW POWDER FOR POWDER METALLURGY

摘要

The present invention provides a method for mixing a raw material powder for powder metallurgy that allows efficient mixing at a low cost with a simple measure and easy adjustment of the apparent density by performing first agitation mixing in which a powder mixture obtained by adding, to an iron powder, one or two or more members selected from lubricant powders, free-machining agent powders, and lubricant powders for sliding surface, an alloying powder, and a binding agent is agitated while increasing the temperature to a temperature T K equal to or higher than the melting point T M of the binding agent, the resultant is agitated while maintaining the temperature T K , and the resultant is further agitated while reducing the temperature from the temperature T K , and performing second agitation mixing in which the obtained powder mixture is agitated while cooling.