Influence of Conditions of the Samples Fixation on the Intensity of the Nanoporous Structure Formation in the Metallic Material by Laser Action with Thermocycling

Abstract

The modes of pulse-periodic laser action with thermocycling were defined, at which an area with a corrugated-shaped relief and a clear border was formed in the center of the heat-affected zone in the study material, brass L62 of 0.05mm thickness. It was found that during pulse-periodic laser action, wedge-shaped submicrocavities were formed on the surface layer of the material. These submicrocavities converge at their edges with formation of extended nanosized channels with widths not more than 100nm. The pulse-periodic laser action with a pulse frequency of 3Hz on single-phase brass leads to the formation of nanosized cavities due to the accumulation of internal stresses during cyclic heating and cooling at high rates. The estimation of vibration rates of the samples in the frequency range from 0.5 to 16000Hz was performed. It was revealed during the study of the forced oscillations that the maximum values of vibration rate occur at frequencies corresponding to the natural vibration frequencies. The application of a damping device causes significant reduction in vibration rate, but under such conditions the pore formation is not stopped. It was determined that the conditions of fixation of the samples during pulse-periodic laser action with thermocycling practically do not influence the intensity of the formation of a nanoporous structure. This provides an opportunity to implement the processes of formation of nanoporous structures in the massive parts of devices and mechanisms, it significantly increases the potential for the practical use of this process.