Abstract: Drilling with twist drill is a very common process in the mechanical manufacturing field, which normally produces large axial drilling force and gives poor surface quality. Ultrasonic vibration assisted drilling (UAD) is a kind of vibration assisted drilling (VAD) technology, which is superimposed ultrasonic vibration with frequency larger than 15 kHz on the drilling tool along the axial direction of the tool. The contacting conditions of the cutting edges of the tool with the workpieces can be improved owning to the periodical vibration, which is helpful to obtain a hole with good quality, especially for the difficult-to-cut material. The classification, the feature and the system constitutions of UAD are introduced. The detailed research progress of UAD is reviewed form the different aspects including the dynamics analysis, the vibration chip-breaking theory, the cutting force, the hole precision and surface quality, the application of UAD on the new materials, and the development of UAD equipment. Based on the analysis on the developing status of UAD and the requirement of hole machining on the difficult-to-cut material, the current problems and the development tendency of UAD are indicated from the aspects of the theory study, the specific ultrasonic vibration system development, the application of UAD on the new materials, the UAD equipment and the normalization and standardization of UAD.

Key words: hole machining, ultrasonic machining, vibration drilling