Research And Development On Vibratory Stress Relief Equipment

Vibratory Stress Relief(VSR) is an effective technical means to average and eliminate the residual stress inside of the workpiece. Compared with traditional methods of natural stress relief and thermal stress relief, vibratory stress relief has advantages of less energy consumption, free of pollution, fast processing and remarkable effect. It is of extremely significant economical and social benefits.Started from the concept and the processing mechanism of residual stress, this paper made an analysis on the mechanism of averaging and eliminating internal residual stress from the perspective of macro-and microscopic view. It analysed the residual stress’s averaging and eliminating process based on metal’s strain-stress mechanism from the macro perspective view. Furthermore,it also revealed the internal relationship between the results of VSR and dislocation’s density and configuration by adopting the dislocation theory. The intrinsic nature of VSR was expounded by means of mathematic. According to the basic theory of vibration,the paper made a theoretical analysis on the method of VSR and discussed the determining principle of pivotal parameters of VSR. It also explored the methods of evaluating the effect of VSR. Theoretical basis was given for system’s software and hardware design.The paper built a VSR equipment. This equipment’s hardware structure is made up of two major parts, which consist of upper computer (industrial computer) and lower computer (AT89C52SCM). The VSR equipment includes a DC vibratory exciter, an industrial computer, vibrating motor control module, an acceleration sensor,an anti-alias filter and amplifier, and the DAQ card PCL-818HG. The DC exciter motor control module’s circuit was designed, at the same time, the main program of upper computer and that of the SCM were completed. There are two functions:the first one is that the DC exciter’s speed is controlled stably by the control circuit based on SCM; The second one is to acquire the vibration signal of the workpiece through DAQ card PCL-818HG. The upper computer completes the spectrum analysis for the vibration signal and then natural frequency of the workpiece will be obtained.At the end, optimum excitation frequency is calculated, then it’s time to implement vibratory stress relief for the workpiece.Finally, several ideas and proposals were put forward on future work for the insufficient and non-completion in this regard.