The Influence of Tempering Parameters on the Microstructure and Mechanical Properties of Heat Treated Low Alloy PM Steels
Tempering is a heat treatment technique used to improve the strength, ductility and toughness of hardened carbon steels. Tempering occurs by heating the steel to below its critical temperature in order to transform the metastable body-centered tetragonal martensite structure that is formed during quenching into a more stable structure of fine carbide particles. Choosing the correct parameters for tempering is critical to achieving the desired balance of properties. It is important to understand the role tempering has onstrength and toughness properties, as well as the microstructural changes experienced over a range of tempering temperatures. This study examined the mechanical performance of two different alloy systems, a prealloyed and a diffusion-bonded material, after being heat treated and tempered at various tempering parameters.