The energy density threshold evaluation for high-precision laser cleaning of the oxidized layer on 7075 aluminum alloy with 100 ns laser

The machining parameters are difficult to duplicate and apply among various equipment in 7075 aluminum laser cleaning. This is due to the non-uniform Gaussian beam being used as the laser source, and the previous mean energy density hardly meets the high-precision evaluation. Therefore, an accurate calculation method of energy density corresponding to the beam intensity distribution is proposed. The key step is to get the intensity distribution of the focal spot. Here, an indirect method for calculating is applied to solve the problem that the focal spot energy is ultra-strong to be directly measured and analyzed. Then, a universal energy density threshold for the oxidized layer laser stripping on 7075 aluminum alloy is studied by analyzing the surface morphology of 7075 aluminum alloy cleaned by 100 ns pulse laser with different laser powers and scanning velocities. This research will provide basic data for high-precision laser cleaning equipment.