Effects of Pulse Duration on Laser Micro Polishing

Abstract

Pulsed laser micro polishing (PLخ¼P) has been shown to be an effective method of polishing micro metallic parts whose surface roughness can approach the feature size. Laser pulse duration in the PLخ¼P process is an important parameter that significantly affects the achievable surface finish. This paper describes the influence of laser pulse duration on surface roughness reduction during PLخ¼P. For this purpose, nearinfrared laser pulses have been used to polish Ti6Al4V at three different pulse durations: 0.65 خ¼s, 1.91 خ¼s, and 3.60 خ¼s. PLخ¼P at longer pulse durations resulted in dominating Marangoni convective flows, yet significantly higher reductions in the average surface roughness were observed compared to the short pulse duration regime without convection.