Efficient coupling of dual beam combined laser into micro water jet for deep processing
Ji Wang, Chunguang Chen, Guolong Wang, Kaijie Cheng, Wenwu Zhang
Abstract
In order to improve the power and energy of water-jet-guided laser, this paper introduces a double beam water-jet-guided laser (DWJL) technology. Based spatially polarized light combination and temporal phase modulation, two lasers are effectively coupled into a water jet with diameter of 100 μm. The maximum output peak power reaches 100 kW and the maximum pulse energy is 4.63 mJ with an operation frequency range from 1 to 20 kHz. The coupling efficiency is as high as 90.4%. Its efficient energy utilization offers new solutions for precision cutting and processing of thick materials. Ultimately, the machining capability of high-power/high-energy DWJL was demonstrated by cutting through 7075 aluminum alloys of varying thicknesses. The cutting depth reaches 10.61 mm, corresponding to a depth-to-width ratio of the cutting gap exceeds 90:1, and the taper is only approximately 0.23°. There is no heat-affected ablation zone on the processed surface. For deep micro holes processing, a minimum radius is 248.54 μm with a depth-to-diameter ratio of 21:1. As the ongoing development of DWJL technology, this innovation is anticipated to find broader applications in aerospace, automotive manufacturing, and high-end equipment manufacturing in the future.