TEMPER: What Metallurgical Characteristics Are Most Influenced by Tempering Low Alloy Steel After Low Pressure Carburizing and High Pressure Gas Quenching

Tempering is the last step of heat treatment to achieve the required metallurgical specifications on low alloy steels following Low Pressure Carburizing (LPC) and High Pressure Gas Quenching (HPGQ) treatments. Time and temperature are THE key variables in achieving the final properties. For this presentation, the ECM USA Synergy Center team performed a series of tests, studied independently, with these two key variables to determine the main effects of this treatment on surface hardness, effective case depth and core hardness. This study was introduced to reduce discoloration of parts by tempering at lower temperature with a longer cycle. Different types of temper will also be discussed in relation to color aspect after tempering.