Effects of Heat Treatment on the Hardness of Mild Steel Using Different Quenchants

This study investigates the effect of different cooling media on the hardness of mild steel after heat treatment. Mild steel samples were heated to 900°C for 45 minutes and subsequently cooled using water, brine, oil, air, and furnace cooling methods. Rockwell hardness testing was performed on each sample, and the results demonstrate a strong relationship between cooling rate and final hardness. Water and brine quenching produced the highest hardness values, while furnace cooling resulted in the lowest hardness. The findings highlight the importance of selecting appropriate quenching media to achieve desired mechanical properties in steel components.