共晶复相陶瓷细观结构对抗冲击强度的影响（英文）

Inherent Relationship between Microstructure Parameters and Anti-impact Strength of Eutectic Composite Ceramic

通过共晶复合陶瓷的细观强度和动态破坏准则建立起微观结构参数与抗冲击强度间的内在关系。首先,根据共晶复合陶瓷的微观特征,用相互作用直推法和有效简化算法获得复合陶瓷的有效应力场。然后,应有等效夹杂法和Griffith微裂纹扩展理论预报了共晶复合陶瓷的细观力学强度。进而,应用统一压剪理论建立冲击区的动态破坏准则。最后,应用与微观结构相关的动态破坏准则建立冲击强度计算模型。定量分析了微观结构参数对冲击强度的影响,结果表明:共晶体间界面缺陷尺寸越小及共晶体刚度越大,抗冲击强度越大。

The inherent relationship between the microstructure parameters and anti-impact strength is established by micromechanical strength and dynamic destruction criterion of eutectic composite ceramic.Firstly,in line with the microstructure characteristic of eutectic composite ceramic,the effective stress field of composite ceramic is computed by the interaction direct derivative estimate and sufficiently simplified calculation method.Secondly,according to equivalent inclusion method and Griffith micro-crack propagation theory,the micromechanical strength of eutectic ceramic composite is predicted.Thirdly,the dynamic destruction criterion of the comminuted zone is built by the unified pressure shear criterion.Finally,on account of the dynamic destruction criterion which is associative with microstructure,the calculated mode of anti-impact strength is obtained.The influence of microstructure parameters on anti-impact strength is quantitatively analyzed.Results show that decrease in interface defect size among eutectic grains and increase in eutectic grain stiffness will increase anti-impact strength.