Effect of Different Welding Parameters on the Mechanical and Microstructural Properties of Stainless Steel 304H Welded Joints

In this research work, an attempt has been made to examine the different welding parameters which affect the weldability of 304H Austenitic stainless steel (ASS) welded joint using the proper filler wire. Chemical composition of filler wire was same as that of base metal. Further this study addressed the combined effect of various welding parameters on the metallurgical and mechanical properties of the weldments. Welding was carried out at different parameters such as welding wire speed, shielding gas flow rate, welding current and arc voltage etc. Tensile tests and V-notch Charpy tests were conducted as per ASTM to determine the mechanical properties of the welded specimens. In order to determine the microstructured changes that occurred, the interface regions of the welded specimens were examined by microscope. As a result, it is reported that changing the shielding gas flow rate and wire feed speed affects the microstructure and mechanical properties of weldment. Impact tests reveal that toughness of the welded joint increases with increasing in welding current, while ultimate tensile strength (UTS) first increases and then decreases.