Formation of the composition and topography of surface layers of Cu$_{50}$Ni$_{50}$ foils under laser irradiation

The influence of the laser radiation power density on the changes in the composition and mechanical properties of surface layers of Cu$_{50}$Ni$_{50}$ foils has been investigated using X-ray photoelectron spectroscopy, scanning probe microscopy, X-ray diffraction, and microhardness measurements. It has been found that, after laser irradiation, the redistribution of elements occurs in the surface layer with a thickness of $\sim$30 nm on the irradiated side of the foil. It has been revealed that there are microdistortions in the crystal lattice of the alloy, microdeformations of grains, and variations in the microhardness of the irradiated surface. The mechanisms explaining the observed changes in the foils after laser irradiation have been proposed.