Vibration Stress Relief Treatment Of Cold Rolled Strip

At present, the application of vibratory stress relief in large castings, forgings, the welded plate has been more widespread promotion, and its related literature and research achievements are many, but on vibratory stress relief treatment of cold rolled strip are few studies that have been reported. In this paper, the method of numerical simulation and experiment was used to establish the vibratory stress relief process of the cold rolled strip, and use the vibratory stress relief treatment on the cold rolled strip.1, a comprehensive analysis of the mechanism of residual stress and the impact on the metal workpieces, and combined with the production process characteristics of cold rolled strip, analysis of the causes of residual stress and its influence on the quality of the strip. Based on the characteristics of stress and strain of metal materials under cyclic loading, the mechanism of vibratory stress relief is discussed from the macroscopic angle. Based on the dislocation motion of the crystal under cyclic stress, the elimination mechanism of residual stress is discussed from the microscopic angle.2, the process of vibratory stress relief is studied. The three technological parameters of vibratory stress relief are as follows: exciting force, exciting frequency, exciting time. In this paper, first of all, combined with the relevant literature, this paper discusses the three process parameters selection method, and then on the vibratory stress relief of the other processes: the choice of excitation position, the workpiece constraints, the evaluation method is described in detail. Finally, according to the production process, size and other characteristics of the cold rolled strip, a clamping device was made to improve the excitation method and prepare for the late vibration stress relief test.3, the dynamic analysis of vibration stress relief. Through the modal analysis, the natural frequency and vibration mode of the cold rolled strip with different tension are solved, which provides a reference for the choice of exciting frequency and exciting position. Based on the harmonic response analysis, the dynamic stress and the amplitude response of the cold rolled strip are analyzed under different excitation technique and different excitation force, which can provide reference for the selection of exciting force. Through the transient response analysis, the process of vibration stress relief is simulated, and the change of residual stress of the cold rolled strip is compared before and after the vibration stress relief.4, the vibration aging test for cold rolled strip. The natural frequency and vibration mode of the vibratory stress relief are measured by the vibration test, which provides an accurate basis for the choice of the exciting frequency and the position of the plate. By using the method of parametric curve, the method of sticking strain on the plate and the effect of X ray, the effect of vibration stress relief was evaluated, and the results showed that the residual stress in the plate was eliminated to a certain extent after the vibration stress relief.