采用喷丸强化和振动冲击强化两种表面形变强化方法改变30CrMnSiNi2A钢的表面完整性,用升降法测定了107循环周次下光滑试样的疲劳极限。试验结果表明,振动强化使疲劳极限提高11%,喷丸强化使疲劳极限提高16%。

The changes of surface integrality caused by shot peening and vibration peening were investigated and its influence on fatigue limit of 30CrMnSiNi2A steel for 107 cycles was determined. Due to the local plastic deformation, residual stresses are developed and the surface topography is changed. Results on the influence of shot peening and vibration peening on 30CrMnSiNi2A steel are compared. The results indicate that the fatigue endurance limit of the shot peened specimens is higher than the corresponding limit of the virgin specimens by about 16% and the fatigue limit of vibration peened specimens is higher than that of virgin specimens by about 11%. The reason why fatigue limit is improved is that surface integrality is modified by mechanical surface treatment such as shot peening and vibration peening.