Effects of heat treatment on microstructure evolution and wear behaviors of 9Cr5Mo roll steel after warm shot peening

Purpose This study aims to reveal the effect of heat treatment (HT) on the microstructure and wear behavior of 9Cr5Mo steel was investigated. Design/methodology/approach The authors HT experiments were conducted on 9Cr5Mo roll steel after warm shot peening (WSP). The effect of HT on the microstructure and wear behavior of 9Cr5Mo steel was investigated. Findings That with increasing quenching temperature, the transformation to tempered martensite and bainite became complete. The increased amount of tempered martensite and bainite and the uniform distribution of carbides increased the hardness and wear resistance. However, higher quenching and tempering temperature and water cooling led to overgrowth of bainite and tempered martensite, coarsening of the microstructure, reduced hardness and decreased wear resistance. With increasing quenching and tempering temperatures, the wear mechanism changed from abrasive and oxidation wear to abrasive, adhesive and oxidation wear. Moreover, the HT parameters that resulted in the best wear resistance were determined. Originality/value HT experiments were conducted on 9Cr5Mo roll steel after WSP confirm that the HT parameters that resulted in the best wear resistance.