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A Micro Ultrasonic Grinding Device with Very High Frequency and its Application

This paper deals with the development of an extremely high frequency ultrasonic transducer of magnetostrictive type with vibration frequency of up to 400kHz, and its application to ultrasonic grinding. This transducer provides longitudinal, torsional and complex modes of vibration. The application of this transducer to grinding or boring on glass, ferrite and alumina ceramic workpieces, resulted in stable grinding force and reduced chipping, especially in the complex mode of vibration. The vibration amplitude of the transducer is controlled to a step of 0.2μm, thus a depth of cut of 0.2μm is realized in grinding on a normal NC machine.