Study On The Radial Vibration Of An Annular Ultrasonic Concentrator With Multiple Radial Slits

In order to improve the quality of metal, the ultrasonic vibration is always introduced in the field of metal molding processing in recent decades, such as the ultrasonic cold drawing metal tubes and wire. The features of the craft are energy saving, and the surface quality, rate of finished and the drawing pass of the product are greatly improved than that of the traditional drawing, In the present, the ultrasonic vibration is exerted along the longitudinal of the material. And also the level of the ultrasonic power combining is lower, only can combining two and below ultrasonic power along the longitudinal directions. The orthogonal composite vibration wire drawing is researched at the craft of ultrasonic wire drawing in the current. This method can decrease the drawing force and improve the surface quality of the material. So the radial vibration characteristics of a annular ultrasonic concentrator is put forward in this article. The concentrator has multiple radial slits. This method not only ameliorates the mechanical behavior of the concentrator but also improves the transverse ultrasonic power synthesis of the material. It has a good prospect in the ultrasonic tube drawing.In this article the characteristic of the concentrator’s radial vibration is researched. The equation of the equivalent circuit, frequency equation and the displacement amplitude magnification coefficient is deduced. The simulation analysis and experimental verification is executed.1. The equivalent circuit, frequency equation and the displacement amplitude magnification coefficient of the thin and thick concentrator is studied. Compare the similarities and differences between the two concentrators. The radial vibration of the two concentrators is simulated.2. A novel concentrator model is established. The radial vibration equivalent circuit of concentrator is deduced. The equation of the radial vibration resonance frequency and of it is obtained. The curve of the displacement amplitude magnification coefficient versus the radius ratio is researched. The FEM simulations were good agreement with the theoretical results.3. The relationship between the radial displacement amplitude magnification coefficient and resonance frequency of the concentrator and the length, the angle and the number of the silts is analyzed. The regular pattern of the displacement amplitude magnification coefficient change with the slit size parameter changes is found.4. It is illustrated that the radial resonance frequency of the concentrator at the first order decreased as the radius ratio increased, and a minimum of the radial resonance frequency of the concentrator at the second order appears with the radius ratio changes. The radial resonance frequency of the concentrator decreased as the length, the angle and the number of the silts increased. The displacement amplitude magnification coefficient increased as the slit length, the angle and the number of the silts increased when vibration outward transfer at the first order and vibration inward transfer at the second order. The magnification coefficient of the second order is even bigger than first order.5. Some concentrators are manufactured based on the result of the theory and FEM simulations. The resonance frequency of the concentrator measured by using the laser vibrometer. The theoretical and FEM results are verified.