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采用压力铸造法，制得Ａｌ２Ｏ３ＳｉＯ２短纤维增强的铝合金复合材料，对其弯曲疲劳性能进行了测试，并详细观察了疲劳裂纹的形成及扩展方式。结果表明：Ａｌ２Ｏ３ＳｉＯ２ｆ／ＺＬ１０８复合材料存在多种疲劳源；疲劳裂纹的扩展是通过主裂纹与裂尖前方孔洞的相互联接而进行的，是不连续的，沿着纤维及渣球密集的路径扩展；疲劳过程中主裂纹的形成消耗了大部分的疲劳寿命，一旦主裂纹形成就快速扩展瞬间断裂。该复合材料的断裂宏观上是脆性的，但微观上显示出塑性的特征。
The pressure-casting method was used to obtain Al2O3SiO2 short fiber reinforced aluminum alloy composites. The bending fatigue properties of the composites were tested. The formation and propagation of fatigue cracks were observed in detail. The results show that there are many kinds of fatigue sources for Al2O3SiO2f / ZL108 composites. The fatigue crack growth is through the interconnection between the main crack and the front of the crack tip, which is discontinuous and extends along the dense fiber and slag spheres. The formation of the main crack during fatigue consumes most of the fatigue life, rapidly expanding the instantaneous fracture once the main crack is formed. The fracture of the composite is macroscopically brittle, but microscopically shows plastic characteristics.