铜在铍晶体中扩散系数和浓度分布的理论研究

Theoretical study on the diffusion coefficient and concentration distribution of copper in the beryllium crystal

摘要:

惯性约束聚变实验中铜在铍晶体中的扩散是影响靶丸性能的重要因素. 采用分子动力学方法研究了铜在铍晶体中的扩散系数，并分析了铜在铍晶体中扩散浓度和深度的关系. 研究结果表明在低温区域铜掺杂浓度较大的体系中扩散系数明显较大. 当铜掺杂浓度为1.0 at%时其扩散系数与实验符合很好. 在靶丸热解条件下使用扩散方程得到铜原子扩散浓度和深度分别为0.06 at%和6.2 um. 10 um厚的0.5 at%铜掺杂层可以降低铜在铍晶体中扩散的深度. 这些研究能为制备性能更高的靶丸提供有用的帮助.

Abstract:

The diffusion of copper in the beryllium crystal is an important factor affecting the performance of the capsule in the inertial confinement fusion experiment. The diffusion coefficient of copper was investigated by molecular dynamics method in the crystal of beryllium, and the relationship between the diffusion concentration and the depth of copper in germanium crystals was analyzed. The results show that the diffusion coefficient of copper atoms is significantly larger when the copper-doped concentration is higher under low temperature conditions. The copper diffusion coefficient is in good agreement with the experiment when the copper-doped is 1.0 at%. The concentration and depth of copper atom diffusion are 0.06 at% and 6.2 m, respectively, under the same conditions as the capsule pyrolysis. A 10 m thick 0.5 at% copper-doped layer can reduce the diffusion depth of copper atoms in the beryllium crystal. These results could provide useful help for the preparation of higher performance capsule.