纤维增强陶瓷中界面层和热应力对基体开裂的影响  

Effects of interface layer and thermal stresses on matrix cracking in fiber reinforced ceramics

作　　者：蔡乾煌[1] 邹毓强 

机构地区：[1]清华大学工程力学系

出　　处：《清华大学学报（自然科学版）》1998年第12期83-87,共5页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金

摘　　要：基于可以考虑界面层效应和界面剪应力作用的三层组合圆筒模型，对纤维增强陶瓷材料分别得到沿纤维方向承受拉伸载荷和热降落引起的应力表达式，包括界面出现剪切滑移和裂纹在基体中扩展后的应力再分配及应力集中。在此基础上建立了可以考虑界面层和热应力影响的基体开裂临界应力求解方程。在不考虑界面层和热应力的条件下其可退化为著名的ＡＣＫ解。最后以材料ＳｉＣｆ／ＳｉＣｍ为例，计算并讨论了界面层和热应力对该临界载荷的影响，得到的理论预估值与实测值有较好的一致。The three cylinder model can be used to consider the effect of interface layer and shear stress. Based on the model, the stress expressions can be obtained, which include the stress re distribution and stress concentration after interface sliding at the fiber matrix interface and crack extending in matrix, when composites objected to uniform applied loading along aligned fiber direction and thermo mechanical loading, respectively. The equation on critical stress of matrix cracking that could consider the effect of interface layer and thermal stress can be obtained. This expression of critical stress can be reduced as famous ACK solution when the effects mentioned above are ignored. For example, composites SiC f /SiC m are evaluated and obtained theoretical values consist well with measured results.

关 键 词：纤维增强陶瓷 界面层效应 热应力 基体开裂 

分 类 号：TQ174.758[化学工程—陶瓷工业]