【摘要】 SiCp/A356复合材料的宏观力学行为与其微观损伤机理密切相关。随着温度的升高,材料力学性能明显下降,SiCp/A356复合材料表现出的微观损伤机理不同。本文建立了球形SiC颗粒与铝基体组成的复合材料单元体计算模型,采用该模型对复合材料的微观损伤机理进行了仿真研究,分析得到的复合材料微观损伤机理与实验观测结果相吻合。在常温下复合材料的裂纹萌生以基体撕裂和颗粒断裂为主;高温下其裂纹萌生机制以颗粒脱离和基体撕裂为主。更多还原

【Abstract】 Macroscopically mechanical behaviors were closely related with the micro-damage mechanism of SiC particle reinforced aluminum matrix composites.With the temperature increasing,the mechanical properties of the composites decreased significantly,the reason of which was the micro-damage mechanism of the composites was different at different temperature.The unit cell model for the SiCp/A356 composites was established which consists of a spherical SiC particle and aluminum matrix.On the basis of the model,the simulation study on the micro-damage mechanism of the composites was carried out.The micro-damage mechanism of the composites from the finite element simulations was consistent with the results from the experimental investigations.It can be concluded that the crack initiation mechanism of the composites at room temperature was mainly tear of the matrix and fracture of SiC particles mainly;while the mechanism of the composites at high temperature was SiC particle debonding from the matrix and tear of the matrix.更多还原