Effect of heat input on the microstructure and hydrogen embrittlement susceptibility of the coarse-grain heat-affected zone of CrMo steels generated using a Gleeble 3500 welding simulator

The changes in microstructure and hydrogen embrittlement (HE) susceptibility of the simulated coarse-grain heat-affected zone (CGHAZ) of CrMo steels under three distinct heat input conditions were investigated. The cooling time from 800 °C to 500 °C, represented by t8/5, increased from 100 s to 200 and 400 s.. The sample with t8/5 = 100 s has a microstructure consisting of martensite and a small amount of lower bainite. When the t8/5 was …