Investigating the Effect of Cooling Media on Hardness, Toughness, Coefficient of Friction, and Wear Rate of Mild Steel Heat Treated at Different Temperatures

Abstract

Mild steel is a common material used extensively in the manufacturing industry. This manuscript investigates the effect of cooling processes on the hardness, toughness, coefficient of friction, and wear rate of mild steel heat treated at different temperatures. The material was heat treated in a furnace at two different temperatures (500 and 900°C) and cooled by water, oil, and air. Microhardness and impact tests were conducted using ASTM E384 and ASTM E23-12C. For dry conditions, the tribology ASTM G99 test standard was used to determine the coefficient of friction and wear rate per sample. The results show that mild steel heat treated at 900°C and cooled with water increased the material’s hardness by 24% and toughness by 23.3% as compared to oil- and air-cooling media. The same heating temperature and water-cooling media produce the material with a low wear rate (3.223E-008).