Optimization of Laser Additive Remanufacturing Process Parameters of H13 Die Steel Based on Response Surface Method

In this study, the central composite response surface method is used to optimize the laser remanufacturing process parameters of H13 die steel, in which the laser remanufacturing process parameters such as laser power(A), scanning speed(B) and powder feeding rate(C) are taken as the optimization variables, and the forming characteristics such as repaired layer width(W), height(H) and micro-hardness(HAR) are taken as the response values, The regression prediction models between process parameters and forming characteristics of the repaired layer are constructed by analysis of variance(ANOVA). Through the establishment of the perturbation plot and three-dimensional response surface plot, the influence of the interaction between process parameters on the forming characteristics of the repaired layer is analyzed. The results show that the width and height of the repaired layer increase with the increase of laser power and decrease with the increase of scanning speed. Increasing the powder feeding rate is helpful in improving the height of the repaired layer, but it is not conducive to the increase of the width of the repaired layer. It is easy to obtain a higher hardness value with increasing scanning speed and laser power. Finally,the optimal process parameters of laser additive remanufacturing of H13 die steel are determined as follows: laser power is 2.8 kW, scanning speed is 4 mm/s, and powder feeding rate is 16 g/min.