Characterization of cryogenic heat treated Vanadis 4 PM cold work tool steel

The amount of retained austenite in the quenched cold work tool steel sample is 17.7%, in the condition of sub-zero heat treated and double tempered samples following by quenching is 1.9% determined by XRD analysis. The types of carbides (MC, M 7C 3, M 23C 6) present in the structure was determined by XRD and SEM-EDS analysis. The hardness of test samples were 865 HV(0.1) for quenched sample and 785 HV(0.1) forth sample subjected to sub-zero treatment and double tempered after the quenching. ► The amount of retained austenite of tested steels were measured by XRD analysis technique. ► It was observed that cryogenic treatment decreases the amount of retained austenite. ► Peak hardness during tempering at 520°C is due to secondary precipitates of MC and/or M 6 C-carbide.