非均匀应变模型分析非对称层状陶瓷的残余应力

RESIDUAL STRESS ANALYSIS IN UNSYMMETRICAL LAMINATED CERAMICS BY NON-UNIFORM STRAIN MODEL

基于非均匀应变模型 ,给出了非对称型层合材料由层间约束引起的层内残余应力的解析表达式。得到层内应力沿长度方向和界面法线方向分布的变化规律。指出非对称型层合材料由于弯曲应力的存在 ,可产生残余弯曲变形并使残余应力沿厚度方向交替变化。材料失效有可能从界面的拉应力层一侧开始。

An analytical formula of calculating residual_stress in laminates with unsymmetrical structure was presented. The regularity of the residual-stress changing along length and normal direction of interface was derived based on a non-uniform strain model. The results indicate that it is possible that both tensile stress and compressive stress exist in the same layer of the unsymmetrical laminates due to the existence of residual bending stress. There is the possibility that the failure of the laminates originates from an inner layer which suffers a tensile stress. The determination of the residual stress distribution is important for studying strengthening design and failure analysis, as well as thermal deformation analysis of the laminates.