Experimental Analysis of Laser and Scanner Control Parameters During Laser Polishing of H13 Steel

Laser polishing is a manufacturing process in which a small amount of material is melted via laser irradiation and molten pool is then redistributed to create a smoother surface finish/superior surface quality. The focus of this study is to generate more comprehensive understanding of the effects that laser and scanner control parameters have on the formation of laser polished lines. A parameter known as “Laser On/Off delay” is varied along with the laser power to study the impact that these parameters have on the synchronization between laser power and beam scanning velocity. It was determined through experimental analysis that the “Laser On delay” parameter plays a significant role on the formation of the laser polished lines, essentially in a region that is outside to the widely characterized “steady state” zone of constant track width. A set of experiments was conducted to identify the combined effect of transient (acceleration/deceleration) phases for laser power and speed on the terminal geometry of the polished line. When the optimal transient combination of power and speed was used, surface quality improvement by 83% (areal surface roughness (Sa) reduction from 1.35 μm to 0.23 μm) was obtained.