Environment-conscious Cu Free Sintered Steels

Abstract

Fe-Cu-C sintered steels are widely used for automobile parts. However, low-cost Cu free general-purpose sintered steels are also required from the viewpoint of recycling because Cu in steels deteriorates their properties. In this study, Mn and Si were selected as new strengthening elements to replace Cu and the effects of additive method and amount of Mn and Si on the strength were investigated by Fe-Mn-Si-C steels sintered in a nitrogen atmosphere with low-oxygen partial pressure. It was shown that the Fe-Mn-Si ternary master alloys were desirable as the additive method, the addition of 1-2 % Fe-Mn-Si master alloys whose Mn/Si ratio (in mass%) was more than 1 showed mechanical properties superior to the Fe-Cu-C sintered steels.