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对ＴｉＯ２－Ａｌ－Ｂ和ＴｉＯ２－Ａｌ－Ｂ２Ｏ３体系制备的两种Ａｌ２Ｏ３和ＴｉＢ２原位粒子增强铝基复合材料进行了动态压缩试验和高温拉伸蠕变试验．动态压缩试验表明，随着应变速率的提高，复合材料的强度和初始加工硬化率明显增加．然而，复合材料中含有的条状Ａｌ３Ｔｉ对复合材料的动态机械响应基本没有影响．透射电镜观察表明，在高应变速率下两种复合材料强度和初始加工硬化率的明显提高可由复合材料基体中位错密度的显著增加来解释．高温蠕变试验表明，两种复合材料均表现出高的显态应力指数和蠕变激活能．复合材料中含有的Ａｌ３Ｔｉ对蠕变速率的应力依赖性（应力指数）基本没有影响，对复合材料的蠕变抗力亦无明显的降低作用．然而Ａｌ３Ｔｉ提高了复合材料蠕变速率的温度依赖性（蠕变激活能）．在引入门槛应力后，两种复合材料的蠕变数据均可由微观结构不变模型来解释．透射电镜观测证实了蠕变前后微观结构的不变性
Two kinds of Al2O3 and TiB2 in-situ particle reinforced aluminum matrix composites prepared by TiO2-Al-B and TiO2-Al-B2O3 systems were investigated by dynamic compression test and high-temperature tensile creep test. Dynamic compression tests show that with the increase of strain rate, the strength and initial work-hardening rate of the composites increase obviously. However, the stripe Al3Ti contained in the composites had no effect on the dynamic mechanical response of the composites. Transmission electron microscopy revealed that the significant increase in the strength and initial work-hardening of the two composites at high strain rates can be explained by the significant increase in dislocation density in the composite matrix. High temperature creep tests showed that both composites showed high apparent stress and creep activation energy. The Al3Ti contained in the composites has almost no effect on the stress dependence of the creep rate (stress index), nor does it have a significant effect on the creep resistance of the composites. Al3Ti, however, increases the temperature dependence of the creep rate of the composite (creep activation energy). After introducing the threshold stress, the creep data of both composites can be explained by the microstructure-invariant model. Transmission electron microscopy confirmed the invariance of microstructures before and after creep