Investigation on the machining mechanism and surface integrity in ultrasonic elliptical vibration cutting of Al-Si alloys

Abstract

The incorporation of reinforcing particles makes the high-quality machining of particle-reinforced metal matrix composites, exemplified by Al-Si alloys, extremely difficult. Ultrasonic elliptical vibration cutting (UEVC) has been proven potentially advantageous in Al-Si alloys machining. Within this article, by combining finite element (FE) and experimental analysis, the machining mechanism and surface integrity of Al-Si alloys under traditional cutting (TC) and UEVC are discussed. The influence of the relative position of particle and cutting path on the coordinated deformation behavior of particle and matrix was investigated. Then, further analysis was conducted on the cutting force, chip formation, surface residual stress, and tool wear mechanism. Finally, the influence of different process parameters on surface integrity was studied in detail. The results indicated that the intermittent disengagement of the tool from the workpiece in UEVC avoids continuous tool-workpiece compression. Additionally, the elliptical trajectory induces friction reversal and facilitates chip removal, suppressing the damage formation. With the characteristics above, UEVC can significantly enhance surface integrity and suppress tool wear. It can also increase surface residual compressive stress and reduce both the mean cutting force and surface roughness. Current findings provide novel insights and practical guidance for high-quality machining of Al-Si alloys by UEVC.