Under nuclear fusion environments, displacement cascades in the potential first protective wall material vanadium (V) and its alloys lead to a large number of point defects. As sink of point defects, grain boundaries are observed to significantly affect the radiation resistance of structured metals. By using potential energy surface searching tools, the interaction between the interstitial-loaded ∑3<110>{111} symmetric tilt grain boundary (STGB) and the point defects in V-based alloy is investigated. For the self-interstitial atoms (SIA)-loaded STGB, the vacancy located within certain distances from the STGB can be effectively annihilated within several nanoseconds via the interstitial emission (IE) mechanism. If an alloy doping interstitial as a Cr atom substitute the SIA, or the vacancy is stabilized by alloy solutes as Ti atoms forming a solute-vacancy complex near the STGB, IE works more effectively with lower activation energy barriers and less thermal activation time. The results indicate that the STGB-induced IE mechanism raises the radiation resistance of the V-based alloy. The results contribute to the micro-structure and constituent optimizations in designing an excellent V-based first protective wall material.

在核聚变环境下，位移在潜在的第一保护层材料钒（V）及其合金中级联，会导致大量点缺陷。作为点缺陷的下沉点，观察到晶界会显着影响结构化金属的抗辐射性。通过使用势能面搜索工具，研究了填隙的∑3 <110> {111}对称倾斜晶界（STGB）与V基合金中点缺陷之间的相互作用。对于自填原子（SIA）负载的STGB，可以通过间隙发射（IE）机制在几纳秒内有效地消除距STGB一定距离内的空位。如果合金间隙中的Cr原子掺杂了SIA，或由于Ti原子在STGB附近形成溶质-空位络合物而使空位通过合金溶质稳定，IE可以更有效地工作，具有较低的活化能垒和较短的热活化时间。结果表明，STGB诱导的IE机理提高了V基合金的抗辐射性。这些结果有助于设计出色的基于V的第一保护墙材料时的微观结构和成分优化。