Experimental study and numerical modelling on multi-pulse laser ablation of aluminium with femtosecond laser

Abstract

An experimental and fundamental study of aluminium ablation using multi-pulse ultrashort laser irradiation at a wavelength of $1.032\mu m$ and a pulse duration of $280fs$ has been carried out. Experiments were performed with different fluences and pulse numbers, and measurements were taken for both ablation depths and diameters. The theoretical investigation proposes a new way to account for incubation in the material based on the experimental measurements obtained. Subsequently, the development of the one-dimensional Two-Temperature Model (TTM) was carried out, which includes the dynamic evolution of the thermophysical and optical properties as well as the incubation effect and the different ablation regimes for multi-pulse. The experimentally measured depth values and those obtained by the developed model are in close agreement for ablation depth across the entire range of fluences studied, therefore, this model provides a reliable tool for determining ablation depths even before material processing begins.