(1. 四川大学 金属材料工程系， 成都 610065;
2. 上海交通大学 金属基复合材料国家重点实验室， 上海 200030)
摘 要: 用挤压铸造方法制备了Mullite/Al-Cu复合材料。用硬度测试仪、差示扫描量热仪(DSC)和透射电镜(TEM)等设备研究了铝基复合材料及其基体合金中Cu含量变化对时效硬化行为的影响，同时还研究了增强纤维对时效相的析出序列、析出相和位错结构的影响。结果表明，无论是在复合材料中还是在基体合金中，随着Al-Cu合金中Cu含量的增加，时效硬化过程均有不同程度的加速；Mullite纤维的引入提高了Al-Cu合金的时效硬度，明显加速了Al-Cu合金的时效硬化过程，对GP区的形成有抑制作用，但不影响基体沉淀相的析出顺序。
关键字: Mullite短纤维； Al-Cu合金； 时效； 位错
short mullite fibre reinforced Al-Cu composites
（1. Department of Metallic Materials Engineering，
Sichuan University， Chengdu 610065， P.R. China;
2. State Key Lab of MMCs， Shanghai Jiaotong University，
Shanghai 200030， P.R.China）
Abstract:Short mullite fibre reinforced Al-3.45Cu，Al-4.05Cu and Al-4.45Cu composites and their base alloys were fabricated by squeeze casting. The effect of variable Cu content on the agehardening behaviour of the composites and the base alloys，the precipitation procedure and the microstructure of dislocation and precipitates have been studied by means of hardness measurement(HB)，differential scanning calorimetry(DSC)and transmission electron microscope(TEM). It is shown that the age-hardening progress is accelerated apparently whether for the composites or the base alloys with increasing the content of copper in the testing materials. The aged hardness of Al-Cu alloys is increased when synthesized with the short mullite fibres，which obviously accelerates the age-hardening progress of Al-Cu alloys and suppresses the formation of GP zones. But the sequence of precipitates has not been changed in the testing composites.
Key words: mullite fibre； Al-Cu alloys； ageing； dislocation
