纵-扭复合振动模式指数型复合超声变幅杆的研究

本文对指数型纵－扭复合振动模式的复合超声变幅杆进行了理论及实验研究，该变幅杆由均匀截面直棒及指数型截面杆组成。文中推出了变幅杆中纵向振动及扭转振动的共振频率方程，通过发迹指数型变截面棒的截面变化规律，实现了同一变幅杆中纵向振动与扭转振动的同频共振。

The longitudinal-torsional composite mode ultrasonic sectional exponential horns

The longitudinal-torsional composite mode ultrasonic sectional exponentialhorns are studied. The horn consists of an untapered metal cylinder and an exponentialhorn, these two parts consist of a half wave vibrator. The resonance frequency equationsfor the longitudinsa and torsional vibrations of the sectional horn are derived. By choos-ing the radius decay coefficient of the exponential horn, the simultaneous resonance ofthe longitudinal and torsional vibrations of the horn is realized. Four sectional hornsare designed and machined, and their resonance frequencies are measured. It is shownthat the measured frequencies are in good agreement with the computed ones, and themeasured frequencies for the longitudinal and torsional vibrations in the horn are also ingood agreement with each other. This kind of horns can be used in ultrasonic machining,drilling and fatigue testing which need very large displacement amplitudes.