纯铝中氦泡分布特点的研究

Study on Distribution Characteristics of Helium Bubble in Aluminum

将工业纯铝抛光后进行He离子注入,注入剂量为3×1020 m-2,注入能量为500keV。利用SRIM软件模拟预测得离子注入后He原子在距表面1.8μm处浓度最高。将He离子注入样品,在190℃时效192h,促进氦泡的形成和长大,用透射电子显微镜观测样品深度方向上氦泡的分布。结果显示,距表面约1.8μm处氦泡密度最大,说明He原子浓度最高,与SRIM软件模拟预测结果一致。同时发现,晶界处氦泡的尺寸较晶粒内的大,说明晶界有利于氦泡的形成和长大;晶界两侧不同晶粒内氦泡尺寸有较大差异,可能是因为晶粒取向不同造成晶粒中氦泡的形核长大过程不同,说明晶粒取向对氦泡的合并长大行为可能有显著影响。

The industrial pure aluminum was implanted by He ion with the dose of 3×10 20 m-2 in the injection energy of 500 keV.The SRIM software was carried to simulate and predict the highest He atom concentration located at the position,and the position is 1.8μm away from the surface.The sample with He ion implantation was aged for 192 h at 190℃to promote the nucleation and growth of helium bubbles.Distribution of helium bubbles in the depth was observed by transmission electron microscope(TEM).The TEM results show that the highest helium atom concentration is at the position of 1.8μm away from the surface,which is accord with the results by SRIM software.It is found that the size of helium bubbles formed on the grain boundary is larger than that formed in grain,which indicates that the grain boundary is beneficial to the formation and growth of helium bubbles.At the same time,there exist large differences about the size of helium bubbles in different grains beside the same grain boundary,which shows that grain orientation may have a significant influence on coalescence and growth process of helium bubbles.