界面强度对柔颗粒增强复合材料破裂特性的影响

Influence of Interface Characteristic on Failure Process and Mechanical Properties of Brittle Composite Matrix with Soft Particle Reinforcement

界面强度对复合材料的破裂特性和破裂机理具有非常重要的影响。研究了不同界面强度的柔颗粒增强脆性基复合材料在单轴拉伸荷载下的力学性能和破坏过程。在细观尺度上考虑了材料介质力学参数的非均匀分布,采用基于细观损伤力学开发的针对材料破坏过程分析的RFPA2D数值模拟程序,对复合材料从裂纹萌生、扩展直至失稳破坏的全过程进行数值模拟。结果表明,当界面结合较强时,复合材料主要发生穿晶破坏,材料韧性较好但强度较差;当界面结合较弱时,复合材料主要产生沿晶破坏,材料韧性较差而强度较好。

RFPA^2D, a numerical code developed based on meso-damage mechanics, is adopted to simulate the whole failure process, i. e, crack initialization, coalescence, propagation and final rupture under uniaxial tensile load. Such failure process of brittle composite, which is reinforced for soft particles with different strength interfaces, has been studied. Inhomogeneity in mesoscale is applied to the matrix, particles and interfaces, respectively. The results show that mechanical properties of interface have significant effect on the composite and its final fracture mechanism. The phenomena of failures happen across the particles and along the interface under different interface strength have been both presented.