含双尺度界面复相陶瓷的细观界面滑移应力
Slippage stress of micro-interface in two-scale interface multiphase ceramics

基于复相陶瓷显微特征和双尺度界面特性，分析含双尺度界面复相陶瓷内的细观界面滑移应力。首先，基于复相陶瓷宏观、细观和纳观弹性性能，计算双尺度界面复相陶瓷产生弹性变形时的细观平均应力场。然后，在纳观界面位移和应力连续基础上，提出了界面应变模型，确定了纳观界面附近纤维和基体内的位移函数，考虑界面应变的突变值与界面模量间的比例关系，根据纳观界面特性和纤维分布形式，确定出弹性变形条件下外载传递到细观界面上的切应力。最后，基于压痕实验测得复相陶瓷细观界面滑移的屈服切应力，得到细观界面滑移应力的理论计算公式并进行了定量分析。结果表明，复相陶瓷内纳观界面弹性模量越小或泊松比越小时，细观界面越易滑移，复相陶瓷越易产生塑性变形。 The slippage stress of micro-interface was analyzed by the microstructure and two-scale interface characteristics in two-scale interface multiphase ceramics. First, the micro-average stress field of the two-scale interface multiphase ceramics was calculated based on the macroscopic, mesoscopic and nanoscopic elastic properties of multiphase ceramics. Interfacial strain model was proposed on the basis of continuity of displacement and stress in nano-interface, and then, the displacement function of fiber and matrix in the vicinity of nano-interface was calculated. Considering the proportional relationship between interfacial strain and interfacial elastic modulus, shear stress under the conditions of external load transfer to the micro-interface was calculated according to nano-interface properties and fiber distribution. At last, combined with yield shear stress of multiphase ceramics which was determined by the indentation test of multiphase ceramics, the theoretical formula of micro-interface slippage stress of multiphase ceramics was obtained. The quantitative results show that the smaller the interfacial elastic modulus and interfacial Poisson's ratio, the easier the interface is to slip, and the easier the plastic deformation of multiphase ceramics. 国家自然科学基金（11272355）