Effects of solutionizing temperature on electrochemical behavior of SLM additively manufactured IN718 alloy

This study explores the effect of solutionizing temperature on the electrochemical properties of Inconel 718 (IN 718) alloy samples produced by selective laser melting (SLM). Solutionizing temperatures of 950°C, 1000°C, 1050°C, and 1100°C were explored, along with a non-solutioned sample to understand the impact of temperature effect on electrochemical behavior. The samples were also characterized to deepen the insights from the experimental results. Hardness testing was conducted to ensure that heat treatment did not compromise the mechanical properties. The results indicated that heat treatment significantly enhances the mechanical strength and corrosion resistance of IN718. The sample treated at 1050°C exhibited superior general as well as localized corrosion resistance. Characterization of the corroded samples showed that the presence of the δ phase and grain growth contributed to these outstanding electrochemical properties. However, at a solutionizing temperature of 1100°C, both mechanical and electrochemical properties were notably reduced, likely due to the absence of strengthening phases in the microstructure.