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为了搞清超声波在拔丝加工中产生降载效应的机理，在自制的超声波拔丝装置上对黄铜丝进行了一系列冷拔加工的实验。结果表明，在模具上施加超声波，可以有效地降低拉拔力，超声波输出功率愈大，拉拔力的降低幅度愈大，在本实验的工况范围内，最大可降低３７％。超声波的降载效果与拔丝速度有关，在相同的超声波功率作用下，拉拔速度愈小，拉拔力的减少幅度愈大。通过对拉拔丝材表面的扫描电镜观察，表明施加超声波还可改善线材的表面质量，减少表层损伤，降低表面粗糙度。提出了一个简化的超声波拔丝拉拔力的计算模型。根据这一模型所得出的超声功率和拔丝速度对拉拔力影响的计算结果与实验结果能较好的吻合，从而初步说明了超声波所产生的减摩降载作用主要是由于模具和线材之间的断续接触和冲击造成的。
In order to find out the mechanism of the ultrasonic wave loading effect in the wire drawing process, a series of cold drawing experiments on the brass wire were carried out on the homemade ultrasonic wire drawing device. The results show that the application of ultrasonic wave on the die can effectively reduce the pulling force. The greater the ultrasonic output power is, the larger the reduction of pulling force is, and the maximum can be reduced by 37% in the working condition of this experiment. The effect of ultrasonic wave loading is related to the wire drawing speed. Under the same ultrasonic power, the pulling speed is smaller and the pulling force is reduced more. Through the scanning electron microscope observation of drawing wire surface, it shows that the application of ultrasonic wave can also improve the surface quality of the wire, reduce surface damage and reduce the surface roughness. A simplified computational model of pulling force of ultrasonic pulling wire was proposed. According to this model, the calculation results of the influence of ultrasonic power and wire drawing speed on the pulling force are in good agreement with the experimental results, which preliminarily shows that the anti-friction and anti-load effect generated by ultrasonic wave is mainly due to the difference between the mold and the wire rod The intermittent contact and impact caused.