The effect of post-weld heat-treatment (PWHT) and vibratory assisted welding (VAW) on hardness of 304L stainless steels material

Welding is the most common and frequently used method to join the components. The fusion welding process is the one that is a commonly used method to join 304L stainless steel materials. The fusion welding process generates much residual stresses within the materials. Residual stresses can be modified by a few techniques like preheating post-weld heat treatment but it takes more time and requires specific tools. Vibratory assisted welding is introduced to reduce welding defects. In this, a comparative study has been carried between post-weld heat treatment and vibratory assisted welding for the hardness of 304L stainless steel. From the test results, Post-Weld Heat-Treatment (PWHT) and vibratory assisted welding are two effective methods to increase the hardness of the weldments. 13% and 18% improvement in the hardness of 304L stainless is observed in the case of PWHT and vibratory assisted welding, respectively, to the conventional welding. Even though both PWHT and Vibratory Assisted Welding (VAW) as exhibiting almost similar results PWHT processes are more time-consuming, costly, and Laborious. From the current research, it is identified Vibratory assisted welding is the best suitable technique for reducing weld defects and enhancing properties.