The investigation of wear and mechanical properties of carburized AISI 8620 steel by powder metallurgy

In this study, the effect of carburizing on tensile strength and wear resistance of AISI 8620 steel were investigated. Firstly, the alloy with 0.25 %C content was pressed at 700 MPa and sintered at the temperature of 1300°C, 1400°C and 1500°C for 1 hr. After determination of ideal sintering temperature, the carburizing process was applied to Alloy 1 and Alloy 2 (0.2 C% and 0.25%C) at 925°C for 4 h. The microstructure of the samples was characterized by Optical microscopy(OM), scanning electron microscopy (SEM). The mechanical and wear behavior of carburized and non-carburized samples were investigated by hardness, tensile and wear tests. The increase in ultimate tensile strength for Alloy 1 and Alloy 2 after carburizing was calculated as 134.4% and 138.1%, respectively.However, the decrease in elongation % for Alloy 1 and Alloy 2 after carburizing was determined as 62.6 % and 64.7 %, respectively. It is reported that the wear depth values of Alloy 2 for non-carburized and carburized conditions under load of 30 N is 231.2 µm and 100.1 µm, respectively. It is observed that oxidative wear changed to abrasive wear for the transition from load of 15N to load of 30N for Alloy 1 and Alloy 2.