On the Processing Feasibility, Microstructure Evolution, and Mechanical Properties of Laser Clad Stellite® 21 Alloy

Abstract

Laser cladding is widely used for feature repair and manufacturing of large structural components. However, due to processing parameters and thus energy densities variation, defects can form in laser clad materials. There is a need to understand the relationship between energy densities and cladding quality. This study therefore investigates the critical parameters in producing structural Stellite® 21 (Co-Cr-MoNiC) alloy by laser cladding. Compared with conventional manufacturing, laser clad materials possess ultrafine α-Co dendrites and σ-CoCr interdendritic eutectics due to the fast cooling rate. In addition, adjustment of the energy densities can help control defects and improve corrosion resistance. The wear resistance, microhardness, and phase analysis in the laser clad materials are also discussed in this work.