强流脉冲电子束辐照下单晶铝中的堆垛层错四面体

Stacking fault tetrahedra in single-crystal aluminum induced by high-current pulsed electron beam

利用强流脉冲电子束技术对单晶铝进行了辐照,并利用透射电镜对强流脉冲电子束诱发的空位簇缺陷进行分析.实验结果表明,强流脉冲电子束能够诱发位错圈、孔洞甚至堆垛层错四面体这种通常在高层错能金属中不能形成的空位簇缺陷,并且三种不同类型的空位簇缺陷的形核过程并不同时发生,三种空位簇缺陷存在着密切的关系.根据实验结果提出了堆垛层错四面体形成与生长机理.

The specimens of single-crystal aluminum were irradiated with high current pulsed electron beam （HCPEB）. The vacancy cluster defect microstructure has been investigated by using transmission electron microscopy （TEM）. The results show that three types of vacancy clusters including dislocation loop, void and even stacking fault tetrahedron （ SFT）, which are not normally formed in metals with high SFT formation energy, can be formed in single-crystal aluminum specimens irradiated with HCPEB. The nucleation process of three types of vacancy clusters do not appear at the same time. There is a close relationship between the three types of vacancy clusters. Based on the experimental results, a possible mechanism of SFT formation and evolution was presented.