Abstract: The influence of heat treating on mechanical properties as well as on the sliding wear gehavior of sintered Fe-1.5Mo-0.7C steels was experimentally studied.The microstruc-tures of sintered steels change from upper bainite to martensite,tempered martensite,pearlite and lower bainite depending on the heat treating conditions.Heat treating increases the hardness of sintered steels but high tempering temperature,i.e.700℃,causes the hardness to be even lower than that of the as-sintered ones.The impact energy of sintered steels increases with increasing tempering temperature and arrives the highest at 700℃，while the steels tempered at 200℃ have the highest transverse rupture strength.Austempering results in fair good overall properties,such as hard-ness,impact energy,and transverse rupture strenght.When the sintered steels were austempered,oil-quenched or tempered belw 400℃ after quenched,the wear coef-ficient becomes considerably lower.Fair high hardness,such as HV30>380,and structures of martensite,tempered martensite or lower bainite are beneficial to low-ering the wear coefficient.Under the wear test conditions given,delanination and oxidational wear are the main wear regimes for sintered Fe-1.5Mo-0.7C steels.Fe3O4 in the wear debris is beneficial to lowering wear coefficient.

Key words: heat treating, sintered Fe-1.5Mo-0.7C steel, sliding wear,