iron powder and mixed powder for powder metallurgy and manufacture of iron powder

摘要

An iron powder and mixed powder for powder metallurgy as raw materials for producing sintered mechanical components by adding Cu powder and graphite powder to iron powder and rolling and sintering the mixture, 0.008 to 0.5 wt.% of at least one kind of element selected from elements having a value of oxide standard formation free energy of not greater than 120 kcal/mol o2 at 1,000 DEG C is contained in the iron powder and not less than 20 % of the element(s) consists of an oxide, while 0.01 to 0.20 wt.% of at least one kind of oxide powder of an element having a value of oxide standard formation free energy of not greater than -120 kcal/mol o2 at 1,000 DEG C is blended in the mixed powder. In this way, diffusion of C (carbon) from graphite added into iron powder particles is restricted at the time of sintering, and dimensional change accuracy of the sintered product is improved. IMAGE