Experimental study on damage mechanism and surface quality optimization of WC-Co by in-situ laser-assisted turning

Abstract

Tungsten carbide (WC-Co) is a material that is frequently employed in the field of optical mold forming. However, the high hardness of WC-Co presents a challenge in machining. In-situ laser-assisted machining (in-situ LAM) has been demonstrated to yield superior outcomes in the machining of WC-Co. In this study, the effect of temperature increase on the removal mode of brittle-plastic transition of WC-Co materials is investigated by thermally coupled finite element cutting simulations. The damage mechanism evolved from the surface defect formation process of WC-Co in in-situ LAM is revealed. The cobalt content was employed as a point of departure for an investigation into the influence of elevated cobalt content on the mechanical and thermal properties of WC-Co materials, with a specific focus on fracture toughness, hardness, and thermal expansion. The results indicate that elevated cobalt content tends to enhance the surface integrity and processing quality of the processed material. The machining parameters of WC-Co in-situ LAM were optimized using surface roughness as a characteristic value and the optimized surface roughness value was reduced by 45.9%. This study offers theoretical guidance for the optimization of WC-Co in-situ laser-assisted processing factors, providing a reference for practical technical applications.