Welding Thermal Cycle Impact on the Microstructure and Mechanical Properties of Thermo–Mechanical Control Process Steels

Steels obtained by the thermo–mechanical control process (TMCP) possess a higher level of strength than conventional normalized steels due to the fine‐grained microstructures generated during TMCP. Such enhancement opens ways to decrease metal construction weight. At the same time, TMCP steels have less thermal stability, in connection with a lot of factors affecting and governing grain growth during the heating of TMCP steels. Herein, the effects of the welding thermal cycle (WTC) on the structure and properties of TMCP steels of ferritic–perlite (S460M) and bainitic (alform 620M) types are systematically investigated.