Sādhanā ( IF 1.6 ) Pub Date : 2020-06-23 , DOI: 10.1007/s12046-020-01396-0 E Kishor , Narasimhan Swaminathan
Boron (\(\mathrm{B}^{10}\))-based materials such as boron carbide (\(\mathrm{B}_4\mathrm{C}\)) are used in control rods of the nuclear reactors because of their high neutron capture cross section and resistance to thermal and chemical degradation. There is an interest to consider other materials that may serve this purpose. In particular, boron-doped diamonds are prospective candidates as they are known to have excellent mechanical strength. In this work, molecular dynamics (MD) simulations are used to characterize and compare the basic radiation damage properties of boron-doped diamond with the stoichiometric formula \(\mathrm{BC}_3\). Only cubic structures of \(\mathrm{BC}_3\) were considered since the experimentally synthesized structure (as per existing literature) was cubic. The basic radiation damage properties compared include threshold displacement energy, primary damage and defect cluster analysis. In addition, the propensity of the material to amorphize under radiation (RIA – radiation-induced amorphization) was also analysed. It was found that the three materials had very similar threshold displacement energies and hence responded to radiation damage in an identical manner. Furthermore, it was seen that none of them were as favourable as the commonly used \(\mathrm{B}_4\mathrm{C}\), as all of them amorphized at lower doses. Consequently, it is concluded that \(\mathrm{BC}_3\), while having excellent mechanical properties, may not have good radiation resistance.
中文翻译:
基于分子动力学的表征和三种立方BC 3多型辐射损伤特性的比较
基于硼(\(\ mathrm {B} ^ {10} \))的材料,例如碳化硼(\(\ mathrm {B} _4 \ mathrm {C} \))被用于核反应堆的控制棒中,因为高中子俘获截面以及对热和化学降解的抵抗力。有兴趣考虑其他可以用于此目的的材料。尤其是,掺硼金刚石是已知的候选材料,因为它们具有出色的机械强度。在这项工作中,使用分子动力学(MD)模拟来表征和比较化学计量公式\(\ mathrm {BC} _3 \)的掺硼金刚石的基本辐射损伤特性。仅\(\ mathrm {BC} _3 \)的立方结构由于实验合成的结构(根据现有文献)是立方体,因此被认为是立方的。比较的基本辐射损伤特性包括阈值位移能,主要损伤和缺陷聚类分析。此外,还分析了材料在辐射下非晶化的可能性(RIA –辐射诱导的非晶化)。发现这三种材料具有非常相似的阈值位移能,因此以相同的方式对辐射损伤作出响应。此外,可以看出,它们都不比常用的\(\ mathrm {B} _4 \ mathrm {C} \)更好,因为它们都在较低剂量下非晶化。因此,得出的结论是\(\ mathrm {BC} _3 \),虽然具有优异的机械性能,但可能不具有良好的抗辐射性。