3D simulation study on the chip formation process in high speed and ultra-high speed grinding of nickel-based superalloy

A three-dimensional finite element simulation model about high speed and ultra-high speed grinding of GH4169 nickel-based superalloy with a single abrasive was established. The evolution process of chip morphology and the change rule of grinding forces under high speed and ultra-high speed grinding conditions were studied. The distribution and change of physical parameters such as stress, strain and temperature in the grinding area were observed. The influences of the grinding speed and the cutting thickness of single abrasive on the chip morphology, the chip forming frequency and the groove uplift characteristics were analyzed. The results show that the sawtooth chip is easy to appear when grinding high temperature nickel-based alloy at high speed. The grinding force changes periodically, and its period corresponds to the formation process of the chip. The temperature, the strain and the strain rate in the grinding process are mainly concentrated in the shear zone, while the stress is concentrated on two sides of the shear zone. With the increase of grinding speed, the spacing between the sawtooth decreases, the degree of serration increases, the sawtooth forming frequency increases linearly, and the groove uplift ratio increases. In addition, the critical forming chip cutting thickness of GH4169 is about 0.3 μm. When the cutting thickness is 0.8 μm, the sawtooth chip will appear. With the increase of single abrasive cutting thickness, the degree of serration will increase, but the chip forming frequency will decrease.