残余应力对加工变形影响的分析与模拟

为了研究材料去除过程中残余应力的重新分布及该过程所引起的工件变形,假设在该过程中没有引入另外的应力,采用理论计算和有限元模拟的方法对含有已知单向应力情况的矩形板进行了求解,计算了在剥层过程中的曲率、挠度和残余应力,并分析了剩余部分的残余应力变化趋势。结果表明理论解与有限元解获得了极好的吻合。采用有限元法进一步研究了材料去除过程中,单向和双向残余应力对加工变形的影响以及最终残余应力分布规律的异同。

Analysis and Simulation of Machining Deformation Resulting from Residual Stress

With the cutting away of parts of a stressed component,the state of residual stress equilibrium is generally disturbed,and the body has to react by deformation.Assuming stresses induced by the machining process itself may be neglectable, analytical method and finite element model,to investigate the relations of redistributed residual stress and deformation during machining,were used to compute uniaxial stressed rectangular plate with a known distribution of residual stress.The redistributed stress and curvature were computed after removing each layer of material,and the changing trend of residual stress during the operation was analyzed.The analytical and finite element result showed in good agreement.In addition,biaxial stressed plate was simulated using finite element and the results were compared with uniaxial case.Finally the differences of displacement and residual stress in remain part were discussed.