An output amplitude model of a giant magnetostrictive rotary ultrasonic machining system considering load effect

Abstract

The load effect is a key factor influencing the amplitude stability of an ultrasonic machining system during processing. To explore the influence of the load, a giant magnetostrictive rotary ultrasonic machining system was designed and fabricated by utilizing giant magnetostrictive materials. Based on the single-degree-of-freedom vibration characteristics of the ultrasonic oscillator, an output amplitude model that considers the load effect was proposed for the system. In order to validate the model, a rotary ultrasonic drilling experiment of quartz glass was performed. A critical cutting ability parameter on the basis of cutting depth for a single abrasive grain was put forward to differentiate between acceptable and unacceptable ultrasonic performance. The actual ultrasonic amplitude in the machining process obtained from the model was explored. The experimental results indicate that the load has a significant effect on the resonant frequency, resulting in a decrease in the actual ultrasonic amplitude. Moreover, the amplitude characteristics can be considerably improved by tuning. The process parameters of the giant magnetostrictive rotary ultrasonic machining system can be optimized by using the proposed model. The results of this study provide reference data for research and development of rotary ultrasonic machining equipment.