Industrial pure aluminum (0.5 wt% impurity elements) was utilized in many investigations of aluminum matrix composites at home and abroad. However, impurity elements in industrial pure aluminum may influence the interface during fabrication of composite at high temperature. Thereby, it is necessary to use high-purity aluminum (impurity elements less than 0.01%) as matrix to enable study the interface reaction between reinforcement and matrix. In this study, stretches of brittle Al4C3 at the fiber/matrix interfaces in Grf/Al composite were observed. The fracture surface of the composite after tensile and bending tests was flat with no fiber pull-out, which revealed characteristic of brittle fracture. This was related to Al4C3, as this brittle phase may break before the fiber during loading and become a crack initiation point, while the corresponding crack may propagate in the fiber and the surrounding aluminum matrix, finally resulting in low stress fracture of composites.
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机译:在国内外对铝基复合材料的许多研究中都使用了工业纯铝(0.5 wt%杂质元素)。但是,工业纯铝中的杂质元素可能会在高温下制造复合材料时影响界面。因此,有必要使用高纯度铝(杂质元素含量小于0.01%)作为基质,以研究增强材料与基质之间的界面反应。在这项研究中,观察到了Gr f sub> / Al复合材料在纤维/基体界面处脆性的Al 4 sub> C 3 sub>的拉伸。拉伸和弯曲试验后,复合材料的断裂表面是平坦的,没有纤维拉出,显示出脆性断裂的特征。这与Al 4 sub> C 3 sub>有关,因为这种脆性相可能在加载过程中在纤维之前破裂并成为裂纹的起始点,而相应的裂纹可能在纤维中传播。以及周围的铝基体,最终导致复合材料的低应力断裂。
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