Dendrite structure and microhardness of as-cast 4Cr5MoSiV1 steel between different homogenisation processes

The dendrite structure and hardness of 4Cr5MoSiV1 ingot at different homogenisation processes were studied in order to identify the most efficient and cost-effective heat treatment for this steel. The microsegregation and microhardness were analysed after different soak-times at 800 or 1200°C for single-stage treatments, and for two-stage treatments of different soaking times at both these temperatures. At the single-stage homogenisation treatment, it would be expected that with the increasing of soaking times, the homogenisation effect becoming better, and the higher temperature soak especially so. However, the two-stage homogenisation treatments could be more effective than single-stage treatment at the higher temperature. The two-stage treatments 800°C/3 h + 1200°C/1 h have better homogenisation effect than 1200°C/4 h. © 2021 Institute of Materials, Minerals and Mining.