利用透射电子显微镜(TEM)详细分析了不同剂量的质子辐照纯铝薄膜样品的微观结构,质子的能量E=160keV.实验表明,质子辐照能够在Al薄膜中诱发空位位错圈,在实验范围内,位错密度随辐照剂量的增加而增加;质子辐照在1×10^11—4×10^11/mm^2范围内随辐照剂量的增加,位错圈数量密度以及位错圈尺寸都随之增加.在较高剂量6×10^11/mm^2辐照下,位错圈数量密度减小,但其尺寸显著增加,空位倾向于形成较大的空位簇缺陷,且样品中出现胞状结构,胞壁之间有角度很小的取向差,这种胞状结构与材料力学性能的退化关系密切.
In this work, we investigated the microstructures of pure aluminum films irradiated with 160 keV proton by varying the irradiation dose. The vacancy clusters induced by proton irradiation in Al films are characterized by TEM, and the density and size distribution are determined. In the irradiation dose range of our studies, the density and size of vacancy clusters and the dislocation density increase with increasing irradiation dose. Our experimental results show that the dislocation density and size of vacancy clusters increase as the irradiation dose increases from 1×10^11 to 4×10^11/mm^2. When the irradiation dose is as high as 6 × 10^11/mm^2, the number density of dislocation loops decreases, while the size of dislocation loop increases obviously. The vacancies tend to form larger clusters, accompanied by the formation of banded structures in the irradiated sample at higher irradiation doses. We found that there were small crystal orientation differences among the boundaries of banded structure. This banded structure is closely related to the degradation of mechanical and physical performance of irradiated material.