Electrochemical analysis of friction welded 17-4 PH stainless steel components manufactured by selective laser melting

17-4 precipitation-hardenable stainless steel (17-4PH SS) finds essential applications in aerospace, chemical processing, and in oil and petroleum industries. The studies related to friction welding on selective laser melted (SLM) components are limited and depend on the material chosen. The present study aims to understand the friction welding of similar 17-4 PH SS fabricated by the SLM technique. X-ray diffraction analysis confirms the presence of austenitic and martensitic phases in both the base metal (BM) and the weld zone (WZ). Due to dynamic recrystallization, the microstructural changes are observed with columnar grains in the BM to refined equiaxed grains in the WZ. The homogenous microstructure is reflected in the hardness measurements of the WZ showing a uniform hardness distribution. Hardness at the WZ is decreased by about 17% than the BM. Corrosion studies through potentio dynamic polarisation analysis reveal that the BM is nobler towards corrosion than the WZ and wrought material. This study would pave the way for future studies on dissimilar weld joint analysis involving 17-4 PH SS.