中文摘要：

选用0．3μm的Al2O3颗粒，制备了体积分数为30％的Al2O3P／2024Al复合材料。利用硬度测试，DSC测试，透射电镜等手段研究了亚微米Al2O3；2024Al复合材料在160℃，175℃和190℃3种温度下的时效硬化行为。结果表明：亚微米Al2O3颗粒的加入使复合材料的硬度显著提高，但时效前后复合材料硬度提高的幅度较基体合金低得多。利用DSC和TEM对时效过程的综合分析表明，亚微米Al2O3颗粒的加入抑制了GP区的形成，提高了S＇相的热扩散激活能，使S’相析出困难。表现为复合材料析出相的数量较少、尺寸较小。

英文摘要：

Age-hardening behaviors of nearly spherical 0.3 μm-Al2O3 particles reinforced 2024Al composites at temperatures of 160℃, 175℃ and 190℃ were studied by means of Brinell-hardness measurement, TEM and DSC. The results show that due to the addition of sub-micron Al2O3 particles, the hardness of the composite was obviously increased. While the age-hardening efficiency of Al2O3P/Al composite was lower than that of the monolithic 2024 alloy. Formation of GP regions was suppressed and the thermal-diffusion activation energy of S＇ phase was increased which made the precipitation of S＇ phase more difficult. And the number and size of precipitates in the composite were relatively less and smaller.