Response surface methodology and optimisation of laser powder bed fusion process parameters for fabrication of pure nickel and Ni-TiC composites

Department of Industrial Engineering, Stellenbosch University, South Africa

^* Corresponding author: natashasacks@sun.ac.za

Abstract

A response surface methodology approach was used to fabricate nickel (Ni) and nickel-titanium carbide (Ni-TiC) composites using laser powder bed fusion. The aim was to determine the optimal process parameters to achieve maximum density and hardness and to investigate the influence of the TiC addition to pure Ni. Process parameters of laser power and scanning speed were selected according to the central composite design of experiments. Regression analysis found the optimal parameter sets to be 195 W and 400 mm/s, and 190 W and 500 mm/s for Ni and Ni-TiC respectively, which yielded relative densities of more than 99 % and a hardness improvement from 163 HV0.5 to 380 HV0.5 with the TiC addition.