强流脉冲电子束辐照诱发多晶纯铝中的空位缺陷簇结构

利用强流脉冲电子束（HCPEB）技术对多晶纯铝样品进行辐照，采用透射电子显微镜详细分析了辐照诱发的空位簇缺陷.HCPEP辐照后，在辐照表层内形成了大量的四方形空位胞，其间包含位错圈和堆垛层错四面体（SFT）等类型的空位簇缺陷.1次辐照后，空位胞内产生空位型位错圈，5次辐照则主要产生SFT；10次辐照后，空位胞内产生的空位簇缺陷主要是位错圈，局部区域也观察到了SFT缺陷，在产生SFT的附近区域具有很低的位错密度或者几乎无位错出现.HCPEB辐照产生的瞬间加热和冷却诱发了幅值极大且应变速率极高的应力，这一因素 关键词： 强流脉冲电子束 多晶纯铝 空位簇缺陷 堆垛层错四面体

The vacancy defect clusters in polycrystalline pure aluminum induced by high-current pulsed electron beam

The specimens of polycrystalline pure aluminum were irradiated with high-current pulsed electron beam （HCPEB）. The microstructure of vacancy defect clusters has been investigated in detail by using transmission electron microscopy （TEM）. The results reveal that large numbers of vacancy cells including dislocation loop and even stacking fault tetrahedra （SFT） can be formed in the specimens of polycrystalline pure aluminum irradiated with HCPEB. For the specimen irradiated with one pulse, vacancy dislocation loops were formed in the vacancy cells. SFTs became the dominating structures after five pulses. For the specimen irradiated with ten pulses, dislocation loops were frequently present and SFTs were only formed in some local zones of vacancy cells. In the vicinity of SFT formation, dislocation-free or very low dislocation densities were observed. It is suggested that high stress and strain rate induced by rapid heating and cooling due to HCPEB irradiation could cause the shifting of whole atomic planes synchronously. This is the more probable mechanism of the formation of SFTs.