Krypton and helium irradiation damage in neodymium–zirconolite
Krypton and helium irradiation damage in neodymium–zirconolite
复制标题
钕锆石中的氪和氦辐照损伤
DOI：
10.1016/j.jnucmat.2010.11.089
复制
发表时间：
2011
影响因子：
3.1
通讯作者：
William E Lee
中科院分区：
文献类型：
--
作者：
M. Gilbert;C. Davoisne;M. Stennett;N. Hyatt;N. Peng;C. Jeynes;William E Lee
作为锕系元素固定化的主要候选者，锆石作为钚处置的潜在陶瓷宿主的适用性，无论是在存储还是地质处置方面，一直是许多研究的主题。本研究的一个关键目的是了解辐射损伤和惰性气体在锆石材料中的调节作用。为此，对多晶（Ca0.8Nd0.2）Zr(Ti1.8Al0.2) o7锆石样品进行了一系列的非原位辐照。锆石样品在ca位点上掺杂Nd3+（作为Pu替代物），并通过在ti位点上取代Al3+来平衡电荷，在1×1014and 5×1015cm−2的影响下用36kr +(2MeV)离子照射，在1×1014、5×1015and 1×1017cm−2的影响下用4he +(200keV)离子照射，模拟α衰变对微观结构的影响。显微结构分析表明，在较低的Kr+浓度下，锆石没有出现损伤，但在较高的36kr +浓度下，锆石完全无定形。同样，氦积累的证据只在最高的4he +丰度（1×1017cm−2）处发现。利用TRIM代码进行蒙特卡罗模拟，预测了氦在720nm深度处的最高富集浓度，与实验观测结果吻合较好。
A leading candidate for the immobilisation of actinides, zirconolite’s suitability as a potential ceramic host for plutonium disposition, both in storage and geological disposal, has been the subject of much research. One key aim of this study is to understand the effects of radiation damage and noble gas accommodation within the zirconolite material. To this end, a series of ex situ irradiations have been performed on polycrystalline (Ca0.8Nd0.2)Zr(Ti1.8Al0.2)O7zirconolite samples. Zirconolite samples, doped with Nd3+(as a Pu surrogate) on the Ca-site and charge-balanced by substituting Al3+onto the Ti-site, were irradiated with36Kr+(2MeV) ions at fluences of 1×1014and 5×1015cm−2and4He+(200keV) ions at fluences of 1×1014, 5×1015and 1×1017cm−2to simulate the impact of alpha decay on the microstructure. Microstructural analysis revealed no damage present at the lower Kr+fluence, but that the higher36Kr+fluence rendered the zirconolite completely amorphous. Similarly, evidence of helium accumulation was only seen at the highest4He+fluence (1×1017cm−2). Monte Carlo simulations using the TRIM code predict the highest concentration of helium accumulating at a depth of 720nm, in good agreement with the experimental observations.