Theoretical and experimental investigations of angular effects in pulsed CO2 laser ablation with fused silica

However, when machining curved optics, the introduction of incidence and path angles inevitably alters laser beam characteristics and complicates path planning. Due to the complex coupling interactions and unique properties of fused silica, the unclear influence mechanism of these angles on laser ablation has become a bottleneck hindering further advancements.

In this study, a three-dimensional multi-physics model was developed to elucidate the underlying influence mechanism. Through comprehensive theoretical simulations, the effects of different incidence and path angles on surface morphology, temperature field, heat-affected zone (HAZ), and thermal stress were systematically investigated. The results demonstrate that the incidence angle modulates ablation quality and thermo-mechanical properties by reducing power density, inducing spot distortion, and lowering material reflectivity.