Optimization of the spark plasma sintering operation conditions for the optimal manufacturing of NiTi-Cu-Mo alloy for high-strength applications

Abstract All material fabrication techniques require optimization of their processing parameters for improved manufacturing conditions and material properties. For the development of materials or components via spark plasma sintering (SPS), such parameters include the sintering temperature, pressure, time, and heating rate. This study developed a ternary alloy of NiTi-Cu-Mo via the SPS technique while optimizing combined four parameters of the SPS technique. The SPS operation conditions that were optimized in this study were designed using the Taguchi Design of Experiment (DOE), considering three levels of sintering temperature, pressure, time, and heating rate, and their effects on the microstructure and nanomechanical properties were evaluated. It was revealed that under the sintering temperature of 1050 °C, time of 10 min, pressure of 45 MPa, and heating rate of 50 °C/min, a better NiTi-Cu-Mo alloy’s microstructure was attained with optimal hardness, elastic modulus, stiffness, and creep resistance. This was credited to optimal densification, diffusion of the atoms, good necking, and reduced porosity at these sintering conditions, which are useful for the development of such alloys.