Correlation of Microstructure with Hardness, Wear Resistance, and Corrosion Resistance of Powder-Injection-Molded Specimens of Fe-Alloy Powders

In this study, the powder injection molding (PIM) process was applied to Fe-alloy powders. Microstructure, hardness, wear resistance, and corrosion resistance of the PIM specimens were analyzed and compared with those of a conventional stainless steel, SS316L. When Fe-alloy powders were injection molded and then sintered at 1200 °C or 1250 °C, completely densified specimens with almost no pores were obtained. They contained 63 to 80 vol pct of hard (Cr,Fe) 2 B dispersed in the austenite or martensite matrix. Since these (Cr,Fe) 2 B borides were very hard, thermally stable, and corrosion resistant, hardness, high-temperature hardness, wear resistance, and corrosion resistance of the PIM specimens of Fe-alloy powders were 2 to 5 times as high as those of the stainless steel. Such property improvement suggested new applicability of the PIM products of Fe-alloy powders to structures and parts requiring excellent mechanical properties.