Study on the Machining Characteristics of SiCp/Al Under Pulsed Laser–Ultrasonic Vibration-Assisted Composite Turning

Owing to their lightweight nature, low coefficient of thermal expansion, and strong wear resistance, aluminum-based silicon carbide composites serve as pivotal components in aerospace applications. Nonetheless, traditional cutting procedures face severe limitations. The abrasive resistance imparted by ultra-hard SiC particles induces severe load spikes and causes significant micro-damage during machining. To overcome these machining barriers, this study introduces a hybrid energy-field approach, namely, pulsed laser–ultrasonic vibration-assisted composite turning (LUAT). To deconstruct the thermo-mechanical coupling mechanism, a two-dimensional finite element simulation framework was constructed to investigate dynamic force responses and transient temperature fields. Leveraging a custom-built hybrid machining system, experimental investigations systematically evaluated dynamic cutting forces, areal roughness (Sa), and micro-scale damage mechanisms across conventional turning (CT), pulsed laser-assisted turning (PLAT), and LUAT processes. The findings confirmed that laser thermal softening lowered matrix deformation resistance, while the high-frequency intermittent contact mode of LUAT effectively minimized average cutting forces compared with all benchmark processes. Operating at 40 W laser power, 600 r/min rotational speed, 4 μm cutting depth, and 2 mm/min feed rate, LUAT achieved its lowest surface roughness of Sa = 0.075 μm, demonstrating a 56% improvement over laser-assisted turning alone. This work provides valuable theoretical and practical insights for advancing the high-efficiency precision manufacturing of hard-to-machine composites with high volume fractions.