Studies on A-TIG welding of 2.25Cr-1Mo (P22) steel

In the present study, 12 mm thick double side square butt joint was fabricated on 2.25Cr-1Mo (P22) steel plates using A-TIG welding process with in-house developed activated fluxes. Microstructure and mechanical properties of the weld joint were characterized. Effect of post weld heat treatment (PWHT) on the impact toughness was studied. In the as-welded condition toughness was found to be 133 J. There was no proeutectoid ferrite in the weld. After PWHT, the toughness of weld was increased to 177 J due to dissolution and coarsening of existing precipitates. A-TIG weld joint of 2.25Cr-1Mo steel exhibited high hardness and good impact toughness in the as welded condition.