颗粒弥散增强型核辐射屏蔽材料强度模型研究

基于微观力学的均匀化理论，旨在从核辐射屏蔽材料的微观结构、物理特性的角度出发，通过多尺度方法研究了材料宏观的机械力学性质.主要研究对象为颗粒弥散增强的孔隙基体材料，推导出了此类复合材料（金属基材料、非金属类材料）的强度准则模型，可预测微观孔隙率与颗粒相体积分数对材料宏观强度的影响.在塑性极限分析法的理论框架下，在介观上成功引入了速度场跳动来描述两相界面间的力学特性，利用刚性核的球体胞元模型进行求解.最后，选用了界面速度为0的速度场对模型进行研究，并初步探讨了界面效应对材料性能的影响.

A Meso-Micromechanics Approach to the Strength Criteria for Particle-Reinforced Radiation-Shielding Materials

Based on the micromechanics homogenization theory, the macroscopic mechanical strength properties of radiation-shielding composite materials were investigated according to their meso-microstructures and local physical properties at micro-scale. Ductile micro-porous materials reinforced with rigid particles were studied. The strength criteria in view of the impacts of porosity and particle volume fraction were derived for metal matrix composites containing hard inclusions as well as other engineering composite materials (polymer matrix composites or geomaterials). Under the framework of the plastic limit analysis approach, the velocity field jump at meso-scale was introduced to describe the interfacial mechanical behavior between the matrix phase and the inclusion phase, and the rigid core unit cell model was applied in solution. In the end the velocity field in which the interfacial velocity equalled 0 was chosen for calculation, and the effects of the interfacial properties on the material strengths were discussed. The results show the effectiveness of the proposed multi-scale analysis framework.