Enhancing the corrosion resistance of selective laser melted 15-5PH martensite stainless steel via heat treatment

The microstructural optimization for selective laser melted 15-5PH stainless steel via heat treatment to enhance corrosion resistance was investigated. The results showed that after aging treatment, Cu-rich nanoparticles (about 10 nm) diffusely precipitated, and approximately 18 similar to 25 % austenite was distributed near the molten pool boundary. The surface potential of the austenite was approximately 15 mV higher than that of martensite by scanning Kelvin probe force microscopy. However, the austenite phase disappeared and the new NbC-(Mn, Si)O duplex particles precipitated after solution treatment and aging treatment, which decreased the pitting corrosion resistance and passive film stability of the SLM 15-5PH stainless steel.