Additive Manufacturing of Co-Cr-Mo Alloy: Influence of Heat Treatment on Microstructure, Tribological, and Electrochemical Properties

Abstract

Co-Cr-Mo alloy samples, fabricated using Laser Engineered Net Shaping – a laser-based additive manufacturing technology, have been subjected to heat treatment to study its influence on microstructure, wear, and corrosion properties. Following L9 Orthogonal array of Taguchi method, the samples were solutionized at 1200°C for 30, 45, and 60 min followed by water quenching. Aging treatment was done at 815 and 830°C for 2, 4, and 6 h. Heat treated samples were evaluated for their microstructure, hardness, wear resistance, and corrosion resistance. The results revealed that highest hardness of 512 ± 58 Hv and wear rate of 0.90 ± 0.14 × 10−4 mm3/N⋅m can be achieved with appropriate post-fabrication heat treatment. Analysis of variance and gray relational analysis on the experimental data revealed that the samples subjected to solution treatment for 60 min, without aging, exhibit best combination of hardness, wear, and corrosion resistance.