Research On Vibratory Stress Relief Technology And Experiment

Residual stress may be formed of metal component in welding, pressing, casting and other many machining. Under many conditions, existing of residual stress will affect mechanic personality of components seriously, therefore, the question of abolishing the residual stress will become the key spot for many scientists and engineers.The traditional methods of abolishing the residual stress are nature stress relief and heat stress relief. Because of energy crisis, vibratory stress relief was studied from 60's. Comparing with the traditional methods, there are many advantages including short investment, short production period, convenience, save-energy and so on.In this paper, the essence of residual stress is lattice distortion, which is illustrated from the point of vibratory stress relief through the mechanic model of residual stress, and to large extent, lattice distortion induced dislocation. The essential approaches of abolishing residual stress are gotten: one is that enough energy is given to metallic atoms that go back to the balance position because of aggravate vibration, which reduces lattice distortion;the other is that metallic atoms in the state of elastic stress become plastic yield, and reduce elastic strain of metal, which arrives at the purpose of reducing residual stress. From the view of the macro and micro, the mechanism of vibratory stress relief is analyzed, with the discussion of relationship between reduction and averaging of residual stress and lattice distortion, the essential conditions of vibratory stress relief dynamic stress are obtained. The factors which affect on the vibratory stress relief process are wholly illustrated based on the relative documents and the materials. The relationship between vibratory stress relief and stability of component size and fatigue life is analyzed. From the view of vibration, the variety tendency of dynamic parameter and the evaluation method of vibration effect are discussed. Residual stress of component is analyzed quantitatively, and the residual stress variety in the process of the vibration is simulated using finite element method, and the effective of vibratory stress relief is tested.