Study on cutting mechanism of mold steel in ultrasonic elliptical vibration cutting with textured tool

Machining of mold steel like STAVAX is still challenging due to significant tool wear. The ultrasonic elliptical vibration cutting (UEVC) that enables dramatic reduction of cutting force is considered as a potential solution. Tool-texturing on the rake face to reduce the friction coefficient between chips and the tool can be another solution as well. Hence, combining these two approaches may provide synergetic effect to further reduce the cutting force. In order to understand this effect, chip formation using these approaches is experimentally investigated. Chip morphology is totally different whether to use UEVC and textured tools. It was shown that the perpendicular pattern to the chip flow direction may enhance the chip-lifting effect during UEVC. Thus, upward force is applied to the workpiece, which causes reduction of thrust force.