Abstract:
Ultrasonic vibration cutting tests were carried out on 90W-7Ni-3Fe alloy and the influencing factors of surface integrity were analyzed. The microstructure morphology, surface structure, residual stress, roughness, surface hardness and crystal dislocation density of the workpiece were studied by experiments. The results show that the ultrasonic vibration cutting method has a smaller roughness than the conventional cutting mode, which has a significant restraining effect on furrows and scales, and has a smaller roughness of workpiece surface, and significantly improves the machining quality. When the same workpiece is cut, the tungsten phase and the bonded phase are located in the metamorphosed layer in the sub-surface region. The thickness of the tungsten phase metamorphosed layer is up to 400 nm, and the thickness of the bonded phase metamorphosed layer is up to 1 μm. The dislocation density of workpiece surface obtained by ultrasonic vibration cutting is relative to conventional cutting. Compared with the matrix hardness, the surface hardness of the samples cut by UEVC and CC is significantly increased, and the surface hardening of the samples cut by ultrasonic is more obvious. The higher residual stress is formed by ultrasonic vibration.