Mullite／Al-Mg-Si复合材料时效行为研究  

Study on Ageing Behavior of Mullite/Al- Mg- Si and their base alloy

作　　者：龙剑平[1] 邓苗[1] 

机构地区：[1]成都理工大学材料与生物工程学院,四川成都610059

出　　处：《中国材料科技与设备》2006年第4期58-61,共4页Chinese Materials Science Technology & Equipment

基　　金：国家自然科学基金资助项目（59631080）;上海交大金属基复合材料国家重点实验室资助项目

摘　　要：选用挤压铸造法制备Mullite／Al-Mg-Si复合材料，采用用硬度测试（HB）、扫描电镜（SEM）、差示扫描量热仪（DSC）和透射电镜（TEM）等手段，研究了莫来石短纤维增强不同镁硅比（Mg／Si=2，Mg／Si〈2，Mg／Si〉2）成份的Al-Mg-Si复合材料及其基体合金的时效行为。结果表明：复合材料具有和基体舍金相似的时效硬化曲线，相同的析出序列；Mullite纤维的引入提高了基体合金的时效硬度，并一定程度地加速了基体合金的时效硬化过程，但对GP区的抑制不明显；Si或Mg元素的富余都加速了复合材料及其基体合金的时效硬化过程，且两类材料的时效峰明显提前。Mullite短纤维与富余的甄或Mg元素对复合材料的时效硬化过程具有交互促进作用。Mullite short fibre reinforced Al - Mg - Si composite were fabricated through squeeze casting. Ageing behavior of mullite/Al- Mg- Si and their base alloy with balanced （Mg/Si=2 ） ratio of Mg/Si, excess silicon （Mg/Si2） and excess Mg （ Mg/Si2 ） compositions have been investigated by means of hardness measurement （HB） , scanning electron microscope （ TEM ）, differential scanning calorimetry （DSC） and transmission electron microscope （TEM）. It is shown that composites and their base alloys have the similian ageing - hardening curves and the same precipitation procedure. The ageing - hardness of Al - Mg - Si alloys are increased when synthenized with mullite short fibres, which also to some content accelate the age - hardening progress of these al- loys, but the fibre does not suppress the GP zone formation. Excess Mg or Si each obviously accelerates the age - hardening progress of composite and its base alloy, what is more, their ageing peaks are obviously advanced. Mullite fibre with excess Mg or excess Si has an reciprocal effect on age - hardening progress of composite.

关 键 词：铝基复合材料 莫来石短纤维 AL-MG-SI合金 时效行为 

分 类 号：TG156.92[金属学及工艺—热处理] TG166.3[金属学及工艺—金属学]