Effect of tempering temperature on the mechanical properties of hardened 1.2842 steel

Tool steels are designed to have high hardness and durability under severe service conditions. These properties are obtained with the selection of optimum conditions for the heat treatment. Generally, after quenching process some austenite is retained in tool steels. It is important to recognize that a balance must be created between the mechanical properties of a component and the optimum percentage of retained austenite for a given application.In this study, the effects of tempering temperature on the mechanical properties of hardened 1.2842 (O2) tool steel were investigated. At different tempering temperatures, volume fraction of retained austenite was estimated and effect of volume fraction of retained austenite on the hardness, impact toughness and tensile properties are discussed.X-ray Diffraction Method was used to estimate the volume fraction of retained austenite in as quenched and tempered specimens. Charpy impact test was used to determine the impact toughness and tensile test was performed to determine tensile properties of 1.2842 steel at different tempering temperatures. Then test results were interpreted and optimum tempering temperature was selected for the selected 1.2842 steel used in this work.