Multiobjective Optimization of 316L Laser Cladding Powder Using Gray Relational Analysis

During laser cladding of repair parts, multiple objectives must be synthesized; however, the multiobjective optimization of laser cladding is difficult. In this paper, the gray correlation of microhardness, residual stress and wear rate is established to transform these three parameters into a single-objective optimization algorithm to perform a gray correlation. By also using response surface methodology to obtain a mathematical model of the gray correlation degree, the model was analyzed and verified by analysis of variance, and the model accuracy was 90%. The optimal process parameters were determined using the gray correlation model, and the maximum gray correlation was 0.9204832, the microhardness reached 203.65 HV, the residual stress was 45.72 MPa, and the wear rate was 1923.56 μm3/N m. The phases and microstructure of the laser-cladded coating were characterized by scanning electron microscopic analysis of a sample prepared under the optimal processing parameters. This study provides guidance for the multiobjective optimization of process parameters for 316L powder cladding.