The effect of barium on the refinement of primary aluminum and on the modification of eutectics in a hypoeutectic aluminum-silicon alloy was investigated. The results indicate that barium not only modifies the eutectic silicon but also refines the primary aluminum and there is a relationship between the retained barium and the second spacing of primary aluminum. Experiments of barium-treated commercial Al-Si hypoeutectic alloy show that barium is a better modifier than sodium when there is a longer holding time.

研究了铬膜和铌膜的复合对锆合金基体上制备的直流磁控溅射薄膜附着性的影响。使用扫描电镜（SEM）观察了膜层界面，用原子力显微镜（AFM）观察了膜层表面，用划痕法测定了薄膜的附着性。结果表明：膜/基界面结合良好，界面成分升降区狭窄；铬膜与铌膜组成的复合薄膜结合紧密；铬膜的组织为致密、边界孔洞少的纤维状晶粒，铬膜厚度为2ìm时，晶粒仍为亚微米级，但晶粒顶面已出现拱形；膜厚同为2ìm时，外层1ìm铌膜+内层1ìm铬膜组成的复合膜的附着性分别是外层1ìm铬膜+内层1ìm铌膜组成的复合膜的2.35倍、2ìm铬膜附着性的3倍，其原因在于膜层组织及力学性能变化、铌膜韧性好和复合顺序。因此，依靠铬膜厚度的增加来提高铬膜保护性的方法具有较大局限性，通过在一定厚度的铬膜外复合铌膜的方法则有较好的可行性。

Recently, the studies on application of rare earth (RE) in spray-welding materials has attracted more and more attention. Iron base fluxing alloy powder has been widely used as spray-welding materials due to some of its advantages, such as lower price and good wear resistance. However, its oxidation resistance at high temperature is poor, therefore, RE has been used to improve its properties in the present study. The iron base fluxing alloy powder containing mixed RE alloy were prepared by using the smelting-atomizing process, the coating samples were prepared by using the oxide-acetylene flame spraying process. And the effect of RE on oxidation resistance of iron base fluxing alloy spray-welding coating has been studied. Moreover, the oxide layer of the coating samples was analyzed by using scanning electron microscope (SEM) and the X-ray of electron dispersion analysis (EDAX). It has been shown that the addition amount of mixed RE alloy of 0.2 wt% is suitable. Based on the experimental results the mechanism of RE function has been discussed.

用挤压铸造方法制各Mullite/Al-Cu复合材料及其基体合金。用硬度测试（HB）、差示扫描量热仪（DSC）和透射电镜（TEM）等手段，研究了温度和溶质原子浓度对复合材料及其基体合金时效行为的影响。结果表明：复合材料和基体合金具有相似的时效硬化曲线及相同的时效析出序列，随时效温度的升高，峰值硬度降低、析出过程加快；溶质浓度升高，峰值硬度升高、析出过程同样得到加快；纤维除了能明显提高Al-Cu合金的时效硬度外，还能加速其时效析出过程，但对GP区的形成具有明显的抑制作用，而对θ相的析出影响不大。

用挤压铸造方法制备了Mullite/Al2Cu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Al2Cu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Al2Cu合金的时效硬度，明显加速了Al2Cu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。