Study on Microstructural and Hardness Changes in Medium Carbon Steel with Heat Treatment at Austenizing Temperature

Heat treatment is an important method in materials engineering to improve the mechanical properties and wear resistance of medium carbon steel, especially in engineering applications that experience high friction. This study aims to examine the effect of heat treatment temperature variations on the surface hardness and wear resistance of medium carbon steel. The procedures involved heat treatment with adjustments to the austenitization temperature, succeeded by quick cooling. Vickers hardness testing, wear trace analysis, and optical microscopy were also employed. The findings indicate that a higher treatment temperature leads to a greater presence of the martensite phase. This, in turn, increases the hardness to 310.5 HV and enhances wear resistance, as evidenced by wear marks that are both narrower and smoother. There is a strong negative correlation between hardness and wear volume, where higher hardness results in lower wear rates. The microstructure formed at high temperatures is more stable and resistant to deformation due to friction, making heat treatment temperature control a key factor in optimising steel surface performance for engineering applications requiring high wear resistance.