Study of the Surface Layers Structure of Fe-Cr-Ni Dispersion-Hardening Alloys after Laser Processing and Nitriding

It is shown that increasing the intensity of laser treatment of VKS-10 steel accelerates the process of subsequent nitriding and formation of nitride phases, and double laser treatment leads to a slowdown in the formation of nitride phases. The aim of the work is to obtain data on the phase composition of Fe-Cr-Ni based alloys after laser treatment with different intensities and subsequent nitriding, as well as to study the patterns of nitride phases formation at the considered types of treatment. The phase composition and true broadening of the maxima were determined by X-ray diffractometry of polycrystalline samples using mathematical techniques to improve resolution. It is found that as the intensity of laser treatment increases, the amount of a solid solution based on γ-Fe and oxide phases increases, as well as the widths of diffraction lines increase. After nitriding, nitride phases CrN, Cr
2
N, Fe
3
N, Fe
4
N appear, their volume fractions increase greatly with increasing intensity of laser treatment, however, with double laser treatment, the proportion of nitride phases decreases.