Surface microstructuring of aluminum alloy 2024 using femtosecond excimer laser irradiation

Surface microstructuring and modification of aluminum alloy 2024-T3 were investigated using a femtosecond pulse laser irradiation. The surface micrographs of the scanning electron microscopy were characterized as a function of incident laser fluence. The surface features ranging from submicrometer to micrometers were developed through the variation in laser fluence and laser pulse count. Results indicated that surface patterns were uniquely constructed in a controlled use of pulsed laser parameters for the ablation. Two ablation regimes were found in the logarithmic dependence of the ablated depth on laser fluence and two components were attributed to the optical and energy penetration. A thermal dynamic model was adopted to analyze the ablation processes, and the theoretical analysis agreed well with the experimental results