Iso-material manufacturing of 304 stainless steel: Microstructure, corrosion-cavitation erosion synergistic behaviour

Different from additive or subtractive manufacturing, iso-material manufacturing (also named isovolumetric manufacturing) was proposed in this work by laser surface melting (LSM), aiming at enhancing resistance to corrosion and cavitation erosion (CE) of 304 stainless steel. Experimental results showed that partial austenite transformed into martensite after LSM. The corrosion resistance of LSMed sample was improved. LSMed sample exhibited enhanced CE resistance, and was 2.5 and 2 times that of untreated sample in deionised water and 3.5 wt% NaCl solution, respectively. The passivation film for LSMed sample exhibited a high re-passive and self-repairing ability of passivation film. LSMed sample in this study exhibits a high or comparable corrosion and CE resistance in comparison with samples prepared by other fabrication method reported previously.