High-power laser surface treatments in the form of glazing, shock peening, cladding, and alloying can significantly affect material tribology. In this paper, effects of laser glazing, laser shock peening, and their combination on the tribological behavior of 1080 carbon steel were investigated. Laser glazing is a process in which a high-power laser beam melts the top layer of the surface, followed by rapid cooling and resolidification. This results in a new surface layer microstructure and properties. Laser shock peening, on the other hand, is a mechanical process in which a laser generates pressure pulses on the surface of the metal, similar to shot peening. Five conditions were evaluated: untreated (baseline), laser shock peened only (PO), laser-glazed only (GO), laser-glazed then shock peened last (GFPL), and laser shock peened then glazed last (PFGL). In pin-on-disc testing, all laser-treated surfaces reduced dry friction, with the GFPL surface having maximum friction reduction of 43%. Under lubricated conditions, all laser-treated surfaces except the PO sample lowered friction. Similarly, all glazed samples reduced wear by a factor of 2–3, while the PO sample did not change wear significantly. These tribological results are associated with changes in the near-surface microstructure and properties.
High Power Laser Developments with Femtosecond to Nanosecond Pulse Durations for Laser Shock Science and Engineering
