Predicting laser polishing outcomes at edge features

The field of laser polishing has grown to include many strategies and materials, but several barriers remain to widespread commercialization of this technology, one being a lack of predictive capability of how laser polishing affects part edge features. The objective of the present work is to present a method of predicting this change in edge geometry and compare the results with experimental observation of laser polishing on blunt, square, and sharp edges. This was done by measuring the edge geometry before and after polishing using optical focus-variation metrology and comparing this with a prediction from a laser polishing simulation. The results showed good agreement in the edge rounding behavior between simulation and experiment except for an asymmetry of the observed polished edge at higher power that is not captured in the capillary smoothing model. This indicates that the present model can act as a good model for predicting edge rounding at lower power conditions, but additional capability in predicting material buildup and displacement at higher power needs to be added for fully predictive capability.