Research on vibration characteristics of porous rectangular hexahedron sonotrode

Rectangular hexahedron sonotrode has remarkable advantage as a platform to realize auxiliary ultrasonic vibration of workpiece with its abundant resonant frequency. However, the three-dimensional coupled vibration characteristics of rectangular hexahedron sonotrode is hard to meet the requirement of ultrasonic assisted micro forming process, which should be made structural optimization for improving its vibration characteristics. In this paper, the basic structure of 20 kHz rectangle hexahedron sonotrode was designed according to the apparent elastic method and R-L square transformer design theory. The influence of number, size and distribution of inner holes and structure transition arc radius was simulated analysed for optimizing the vibration properties of the sonotrode. The results show that the optimized rectangular hexahedron sonotrode can realize the conversion of ultrasonic vibration direction and get uniform vertical vibration amplitude on the whole radiant surface, so as to meet the requirement of ultrasonic assisted micro forming processing.