Surface integrity of high volume fraction SiCp/Al composite in laser-induced oxidation assisted milling

Low machining efficiency, severe tool wear, and poor surface quality are the main issues when milling high-volume-fraction SiCp/Al composite materials. A revolutionary technique known as laser-induced oxidation-assisted milling (LOAM) has been presented as a solution to these problems. This technique creates a porous oxide layer on 55vol% SiCp/Al composites by using pulsed lasers. By effectively removing the oxide layer, a milling tool can greatly minimize tool wear. To evaluate the feasibility of this process, surface integrity studies were conducted on machined workpieces. Two oxidation strategies were applied during LOAM processing, and comparative experiments were performed using conventional milling (CM). According to the experimental findings, the LOAM process significantly improves the machined workpieces’ surface quality. This improvement is primarily attributed to the pulse laser-induced reaction and decomposition of SiC particles into finer particles, as well as the smearing effect of the Al matrix. Additionally, the LOAM process has been shown to increase the microhardness of machined workpieces. Analysis of EBSD data reveals that grain refinement and twin formation, resulting from deformation, are the main factors contributing to workpiece hardening. However, the LOAM process induces residual tensile stress in the workpiece matrix, which negatively affects its mechanical properties. In conclusion, the laser-induced oxidation-assisted milling process is both feasible and advantageous in specific application scenarios.