Analytical Modeling of Abrasive Grain-Workpiece Cutting Coefficient and Experimental Investigation on Tangential Ultrasonic Vibration-Assisted Forming Grinding Gear

Gear plays an important role in transmitting motion and power systems, and innovative processing techniques are required to enhance their machining accuracy and performance. In this paper, the ultrasonic vibration was applied to the gear, yielding the tangential ultrasonic vibration-assisted forming grinding gear (TUVA-FGG). Firstly, the kinematics of a single abrasive grain in the TUVA-FGG was analyzed. Then, the grain-workpiece separation characteristics were analyzed for various processing (grinding wheel speed and feed rate) and ultrasonic amplitude (frequency and amplitude) parameters. A theoretical model of grain-workpiece cutting coefficient (GWCC) was established, and the effects of ultrasonic and processing parameters on GWCC were analyzed. Finally, the experiments of TUVA-FGG and conventional forming grinding gear (C-FGG) were conducted to verify the theoretical model’s ability from the grinding effect (grinding force, grinding temperature, and surface roughness). In addition, the effects of grinding wheel speed, feed rate, and ultrasonic amplitude on the grinding effect in the TUVA-FGG were explored. It was concluded that in the TUVA-FGG, the normal grinding force, tangential grinding force, grinding temperature, and surface roughness were maximally reduced by 38.6%, 36.2%, 26.9%, and 21.3%, respectively, and the surface quality was effectively improved compared to the C-FGG. This study contributed to the clarification of the GWCC role in the TUVA-FGG grinding effect.