Simulation of Damage Evolution of SiCp/Al Materials under Thermal Cycling Loading

SiCp/Al材料制动盘在频繁的高温环境下，其组织性能必然会发生变化。为阐明SiCp/Al材料服役过程中微观损伤演变规律与机制，借助Abaqus软件构建了SiCp/A356复合材料热损伤的RVE仿真模型并进行仿真分析。结果表明：SiCp/Al材料在上限温度不高于200℃的热循环时，无明显的基体损伤和界面开裂，热循环温度决定材料微观结构损伤模式与程度；热循环中SiCp/A356复合材料颗粒尖端区域和间距较小的颗粒之间的基体承受较大热应力，热应力大小与分布是SiCp/A356制动盘摩擦面热裂纹的萌生与扩展主要驱动力。论文研究对SiCp/A356复合材料制备及其制动盘的成形质量控制具有重要的工程指导价值。The microstructure and properties of SiCp/Al brake discs are bound to change under frequent high-temperature environments. To clarify the evolution law and mechanism of microscopic damage of SiCp/Al composites during service, an RVE simulation model of thermal damage of SiCp/A356 composites was constructed with the aid of Abaqus software and simulation analysis was carried out. The results show that when the SiCp/Al composites undergo a thermal cycle with an upper limit temperature at most 200˚C, there is no obvious matrix damage or interface cracking. The thermal cycle temperature determines the mode and degree of microstructure damage of the composites. Under the action of thermal cycling loading, both the matrix located at the particle tips and the matrix between the particles with a smaller spacing are subjected to large thermal stresses in the SiCp/A356 composites. The magnitude and distribution of thermal stresses are the main driving forces for the initiation and propagation of thermal cracks on the friction surface of the SiCp/A356 brake disc. The research has important engineering guiding value for the fabrication of SiCp/A356 composites and the forming quality control of brake disc.