Nanosecond laser interaction with Beryllium: study of surface erosion and material removal dynamics

• Nanosecond laser fluence steers beryllium surfaces from ripples to craters. • Higher pulse frequency intensifies melt flow, accelerating Be material loss. • Modeling links plasma heat transport to observed laser–induced Be erosion. • Laser–ablation Be droplets model debris behavior in precision optical processing. This study systematically investigates the surface erosion mechanisms and material removal dynamics of beryllium targets subjected to nanosecond pulsed laser irradiation at 1064 nm wavelength, exploring the influence of varying laser fluences (1–3 J/cm 2 ) and pulse repetition rates (5 Hz and 10 Hz). By applying different surface characterization techniques, significant morphological transitions from minimal surface disruption at lower fluences to pronounced craters and complex ripple formations at higher fluences are revealed. Results indicate that increased pulse repetition rates exacerbate thermal accumulation effects, enhancing material removal through intensified melting, evaporation, and the ejection of molten droplets. Complementary hydrodynamic simulations employing the HELIOS code further elucidate the underlying plasma and thermal dynamics, providing detailed temperature and density profiles consistent with experimental observations. This combined experimental and theoretical approach advances the fundamental understanding of beryllium behavior under high-energy laser processing conditions, presenting valuable insights critical for optimizing its performance in precision manufacturing and high-energy technological applications.