Abstract: The grinding temperature in the wheel-workpiece contact zone in the high efficiency deep grinding (HEDG) of silicon nitride is measured by using a grindable K type thermocouple. The effects of grinding parameters on the grinding temperature and on the energy partition are investigated. The results indicate that in the HEDG of silicon nitride, the grinding zone temperature is generally between 200 and 300 ℃, and the partition coefficient of grinding energy is between 2% and 5%, which means most heat is carried away by grinding chips and coolant, thereby avoiding the high temperature in grinding zone. The grinding zone temperature exhibits a sound linear relationship with the average heat flux, i.e. the higher the heat flux, the higher the corresponding grinding zone temperature will be. However, when the wheel linear velocity or the grinding depth exceeds the critical value, the grinding zone temperature will first rise gradually to 250 ℃, then rapidly rise to nearby the temperature of dry grinding.

Key words: Energy partition, Grinding temperature, High efficiency deep grinding, Silicon nitride, composite geologic structures, interfacial contact stiffness, nonlinear, normal stiffness, supporting system of tunnel boring machines