The Study of Ultrasonic Relaxation of Residual Stresses of Metal Plates Using Computer Simulation

To stabilize the geometric parameters of the elastic plates during production, the "aging" method is used, which has low performance, and as an alternative to which the method of ultrasonic stabilization is developed. The essence of ultrasonic stabilization is to create the elastic strain applied via the static load in the central part of the plate by the tool, and to communicate ultrasonic vibrations, which lead to the relaxation of residual stresses and stabilization of the geometric parameters of the plate. Analytical expressions are obtained in order to calculate technological parameters of the ultrasound processing. Computer simulation was held on the basis of the theoretical and analytical models, which has allowed to identify and to visualize the dependence of residual stress and plate deformation on the duration and amplitude of ultrasonic vibrations. On the basis of the obtained dependences it was found that the vibrational amplitude should be reduced to reduce the residual strain, however this increases the processing time. Thus, the greater the amplitude of the ultrasonic vibrations is, the more intense the reduction of residual stresses is. Intensive changes of the residual strain and stresses in the first few seconds are characterized by high efficiency of ultrasonic stabilization, which is recommended as a replacement for the aging method.