Effect of temperature on the material removal mechanism of LIPAA process

Abstract

Laser induced plasma assisted ablation (LIPAA) is a new processing technology for transparent hard and brittle materials. During LIPAA processes, high temperature plasma thermal ablation and ion mechanical removal are coupled in the process of material removal. In this paper, an experimental method to study the effect of temperature on LIPAA process was presented. By using different metal targets (pure copper and pure iron) to carry out LIPAA processing experiments on sapphire C surface, the single-pulse energy threshold, microgroove morphology, microgroove surface roughness, material removal rate and temperature field of the processing area were compared. It was verified that the thermal properties such as the thermal conductivity of the metal target had a great influence on the processing results. The molecular dynamics simulation method was introduced to assist the theoretical analysis. The results showed that the material removal mechanism of laser-induced plasma processing sapphire was mainly thermal ablation. The mechanical energy generated by the shock wave of the plasma plume would assist the thermal energy to remove the material. The research results have guiding significance for exploring the sapphire LIPAA processing mechanisms at different temperatures and different targets.