Multi-objective optimization of high power diode laser surface hardening process of AISI 410 by means of RSM and desirability approach

In this research, laser surface hardening of AISI 410 was carried out by a high power diode laser based on Response Surface Method (RSM). Laser power, scanning speed, and focal plane position were evaluated as input process changeable while geometry dimensions of hardened zone (i.e., Depth and width of hardness), maximum hardness, Microhardness deviation (MHD) from base material in depth, and ferrite phase percentage in the microstructure were evaluated as process output Results. The effect of input parameters on the response variations were studied by statistical investigation. Results indicated that by increasing the laser power and decreasing other parameters, higher surface hardness with significant penetration, and least ferrite percentage would be reached by means of the desirability function approach. By using experimental tests, validation of optimized results was performed. In this research in the optimum conditions, the maximum hardness, maximum depth of hardness and minimum ferrite percentage were achieved 670 Vickers, 2.2 mm and 0.45%, respectively.