(1) Influence of cutting blade size
By changing the cutting blades of different lengths and widths (the thickness is constant) and matching with the transducer, under the finite element analysis, the law of the overall natural frequency decreases with the increase of the blade length, and the law of the decline is basically linear. When the blade width becomes larger, the overall natural frequency also decreases, and the downward trend is larger. In addition, as the length of the blade increases, the magnification (Am) of the combination of the ultrasonic horn and the cutting blade increases. As the blade width decreases, the magnification increases slightly. Therefore, the overall natural frequency and amplitude amplification factor can be adjusted by selecting the appropriate length and width.
(2) Influence of cutting blade material
Changes in the material of the cutting insert necessarily have a certain effect on the acoustic parameters of the assembly. In order to study the effects of material properties without compromising usability, the selected blade materials were cemented carbide and aluminum. The influence of the blade material on the overall ultrasonic properties was analyzed by the finite element method. It can be concluded from the simulation results that the selection of hard aluminum as the cutting blade material has little effect on the natural frequency of the composite; when the material is cemented carbide, the natural frequency variation range Very big. From the results of finite element analysis of amplitude amplification, the change of material properties has little effect on the amplitude amplification.
The addition of the cutting blade causes the overall natural frequency to drop. In order to match the frequency of the ultrasonic transducer, increasing the natural frequency of the ultrasonic horn can reduce or even offset the frequency drop caused by the addition of the cutting blade. The results obtained by experiments are very close to the results of the simulation.