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利用自行研制的冲击拉伸实验装置对单向石墨纤维增强铝基复合材料实施了不同应变率下的拉伸实验。获得了材料在００００５～１３００ｓ－１应变率范围内完整的应力应变曲线。结果表明Ｇｒ／Ａｌ的应力应变曲线可分为两个部分：非线性弹脆性变形以及材料失稳后的残余变形。实验结果还表明Ｇｒ／Ａｌ是一种应变率敏感材料，随着应变率的提高，材料的拉伸强度、失稳应变以及剩余应力均相应提高。根据不同应变率下的实验结果，提出了计及应变率强化效应的复合丝束统计本构模型，模型拟合的结果与实验结果吻合得很好。拟合结果还表明，特征纤维统计分布的Ｗｅｉｂｕｌ参数（尺度参数与形状参数）均是与应变率无关的，复合材料的应变率效应主要是由基体的应变率强化效应引起的。
Tensile tests at different strain rates were carried out on unidirectional graphite fiber reinforced aluminum matrix composites by using the impact tensile test device developed by ourselves. The complete stress-strain curve of the material in the strain rate range of 00005 ~ 1300s-1 was obtained. The results show that the stress-strain curve of Gr / Al can be divided into two parts: the nonlinear elastic brittle deformation and the residual deformation after material instability. The experimental results also show that Gr / Al is a strain rate sensitive material. With the increase of strain rate, the tensile strength, instability strain and residual stress of the material increase correspondingly. According to the experimental results under different strain rates, a statistical constitutive model of composite tow considering the strengthening effect of strain rate is proposed. The results of model fitting are in good agreement with the experimental results. The fitting results also show that the Weibul parameters (scale parameters and shape parameters) of the statistical distribution of the characteristic fibers are independent of the strain rate, and the strain rate effect of the composite material is mainly caused by the strain rate strengthening effect of the matrix.