27th IFHTSE CONGRESS & EUROPEAN CONFERENCE ON HEAT TREATMENT 2022

This work addresses the influence of the quenching and partitioning (Q&P) heat treatment parameters on the mechanical properties and hydrogen embrittlement (HE) resistivity of 20MnSi wire rod steel. The retained austenite (RA) volume fraction in Q&P heat-treated wires is responsible for the high ductility. However, its influence on hydrogen embrittlement resistivity is still controversial in the literature. The RA volume fractions gained from different Q&P heat treatments and their morphology were determined using different techniques. The hydrogen embrittlement susceptibility was measured using an incremental step load test (ISLT) technique according to standard ASTM F1624-12. The results show that heat treatment parameters do not significantly affect strength ~ 1300MPa. However, the partitioning time tP has the highest impact on ductility and hydrogen embrittlement index (EI) provided that the relative EI could be improved from 46,7% to 35.5% due to increasing the partitioning time from 420s to 1800s