Effect of Nanosecond Laser Texturization on Tribological Behavior of AISI 321 Stainless Steel

This study investigates how laser-induced surface modifications influence key properties such as wear resistance, hardness, and friction in dry and lubricated conditions. The research applies nanosecond pulsed laser treatment to create random, quasi-random, quasi-periodic, and periodic surface structures on the steel surface, aiming to enhance the wear resistance and reduce the coefficient of friction (COF). The frictional performance between the carbon steel ball and the texturized surface was evaluated, including an analysis of the initial friction phase contact (single, double, and multi-contact), with the surface topography assessed before and after wear. The results of the pin-on-plate tests indicate that laser texturing improves the hardness by transforming austenite into martensite, modifies the wettability by periodizing the surface, reduces the COF, and enhances the wear resistance. Periodic surface structures allow for better lubricant retention and change in the lubrication regime, contributing to lower friction and a longer surface lifespan. Minimizing ball-surface contact through appropriate surface periodization significantly affects the load transfer. The primary wear phenomena are the adhesive and abrasion wear of a two-body nature, transforming into a three-body one. The study concludes that laser surface texturing is an effective method for enhancing the tribological performance of AISI 321 steel, with potential applications in industries requiring high wear resistance.