Optimization of laser cladding process using taguchi and EM methods for MMC coating production

This study investigates the influence of laser cladding parameters on the geometry and composition of metalmatrix composite (MMC) coatings. Composite coatings are made of a Ni-Cr-B-Si metallic matrix and of WC reinforcement with a volume fraction of 50%. Optical microscopy is used to characterize the coating geometry (height, width, and penetration depth) and to determine the real volumetric content of WC. Laser cladding on low-carbon steel substrate is carried out using a cw neodymium:yttrium-aluminum-garnet (Nd:YAG) laser, a coaxial powder injection system, and a combination of Taguchi and EM methods to design the experiments. This combination explores efficiently the multidimensional volume of laser cladding parameters. The results, which express the interrelationship between laser cladding parameters and the characteristics of the clad produced, can be used to find optimum laser parameters, to predict the responses, and to improve the understanding of laser cladding process.