Optimation of laser modified surface layer homogeneity

The paper deals with an evaluation of homogeneity of laser modified surface layer of martensitic steel grade 21H12NMFA. The authors trying to find an optimum values of control parameters of high power laser machine with beam of which the surface layer of specimens was modified. As the examination of layer homogeneity a nondestructive electromagnetic method has been chosen. For verification purpose of the method the microhardness measurements were applied. In both cases the results of measurements made it possible to reconstruct the surface layer and to visualize it with computer color mapping on base of which the homogeneity of the layer was evaluated. As an example the evaluation procedure was applied to two specimens, namely No14 for which an optimal parameters of laser treatment were achieved and No 15 which found to be in the center of Kiefer's optimization plan.