Effects of Aging Treatment on Microstructure, Mechanical Properties, and Wear Characteristics of 17-4PH Produced by Selective Laser Melting

Additive manufacturing (AM) involves the layer-by-layer deposition of materials and has achieved significant advancements in industry. In this study, we manufactured 17-4PH steel, the most commonly used metal in the selective laser melting (SLM) process, and conducted heat treatment at temperatures of 420°C, 480°C, 540°C, and 600°C for 4 hours. The effects of heat treatment on wear characteristics, strength, and tensile properties were compared and investigated. The experimental results showed that the wear and tensile characteristics of the aged specimens were improved. When comparing the results of specimens aged at various optimal heat treatment temperatures, excellent mechanical property effects were observed. It was confirmed that excessive aging treatment led to a decrease in mechanical properties such as elongation and strength. Additionally, microstructural observations revealed a transformation of the precipitate shape from rod-like to spherical. Compared to the 17-4PH metal matrix AS specimens heat-treated at 540°C, the wear width decreased, indicating that the aged 17-4PH specimens exhibited improved wear resistance.