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采用搅拌铸造法制备了体积分数为6%的SiCp/6061复合材料。通过高温蠕变试验、金相观察(OM)、断口形貌扫描(SEM)及能谱分析(EDS),研究其不同温度下的蠕变性能并分析蠕变断裂机制。结果表明:温度对SiCp/6061铝基复合材料的高温蠕变性能有很显著的影响,温度越高,蠕变性能越差;在250℃、80 MPa的应力下,SiCp/6061铝基复合材料的蠕变寿命约为14 h,而6061铝合金经280 min即发生断裂。由此可以认为,SiCp/6061铝基复合材料比基体合金具有更好的抗高温蠕变能力;复合材料的蠕变断裂机制是首先沿SiCp/Al界面产生塑性撕裂的裂纹源,微裂纹沿晶界扩展,最终发生断裂。
SiCp / 6061 composites with a volume fraction of 6% were prepared by a stirring casting method. The creep behavior at different temperatures and the mechanism of creep rupture were analyzed by high temperature creep test, metallographic observation (OM), fracture surface scanning (SEM) and energy spectrum analysis (EDS). The results show that the temperature has a significant effect on the creep property of SiCp / 6061 aluminum matrix composites. The higher the temperature, the worse the creep property. Under the stress of 250 MPa and 80 MPa, the SiCp / 6061 aluminum matrix composites Creep life of about 14 h, while the 6061 aluminum alloy rupture after 280 min. It can be concluded that the SiCp / 6061 aluminum matrix composite has better resistance to high temperature creep than the matrix alloy. The creep rupture mechanism of the composite is firstly the source of the plastic tear along the SiCp / Al interface, Grain boundary expansion, eventually breaking.