Modification of the roughness of 304 stainless steel by laser surface texturing (LST)

Surface texturing is one of the most effective approaches to modifying the surface to improve many properties: tribological, corrosion resistance, microhardness and others characteristics of a number of engineering materials. Among the surface texturing techniques developed in recent years, the most widely used method is the laser surface texturing method (LST) due to its high flexibility, superior texturing accuracy and good process controllability and reproducibility. With its rapid development, LST has attracted considerable attention in various industries such as automotive, biomedical and aerospace. The present study considers the changes in roughness in different modes of laser texturing of stainless steel specimens 304. The effects and role of individual laser parameters on the change in roughness are analyzed as a main characteristic of the surface properties of the processed material. Heating and its surface melting is one of the studied effects and its role in changing the roughness. The focus of the study is on the process of laser-material interaction as a function of absorbed energy density, pulse frequency, scan rate, and overlap coefficients leading to different effects of LST parameters. It has been found that increasing the energy density, accompanied by a decrease in the frequency and speed of scanning, can increase the surface roughness.