RAFM钢中H+辐照空位型缺陷的慢正电子束研究

摘要

为研究低活化铁素体/马氏体(Reduced Activation Ferritic/Martensitic,RAFM)钢的辐照损伤机理,利用慢正电子技术研究了H+辐照RAFM钢时所产生的空位型缺陷及其对于材料微观结构的影响.H+能量和剂量分别为100 keV和1×1015 cm?2、1×1016 cm?2、1×1017cm?2.慢正电子束多普勒展宽测量结果可得,S参数随着剂量的增大而增大,W参数呈现正相反的趋势.样品中主要辐照区域为142~348 nm,此范围内有大量缺陷产生,辐照产生的主要为空位型缺陷,其中多为氢-空位复合体缺陷,辐照缺陷的浓度随着H+剂量的增大而增加.空位型缺陷的尺寸大小也随着辐照剂量的增大而有所变化,辐照剂量达到1017 cm?2时,S-W曲线斜率发生变化,故辐照缺陷类型发生明显变化,有较大尺寸的缺陷产生.%[Background] RAFM steel is a good candidate structural material and is widely accepted today as a fusion reactor core material. [Purpose] This study aims to investigate the radiation damage mechanism of reduced activation ferritic/martensitic (RAFM) steel, the vacancy-type defects and their effects on the material structure of RAFM steel irradiated by H+were probed by slow positron beam. [Methods] The experimental sample was RAFM steel based on Fe-9wt.% Cr. H+ion beam energy was 100 keV whilst the dose was set to be 1×1015 cm?2, 1×1016 cm?2, 1×1017 cm?2, respectively, for irradiation experiments. [Results] The results of slow positron beam Doppler broadening measurement were available. The S parameter increased with the increase of dose, and the W parameter shows the opposite trend. The main irradiation area of the material was 142~348 nm, there were a large number of defects in this range, the irradiation mainly produced vacancy-type defects, most of which were hydrogen-vacancy complex defects. The concentration of irradiation defects increased with the H+doses. [Conclusions] The size of the vacancy-type defect changes with the dose increase. When the irradiation dose reaches 1017 cm?2, the slope of the S-W curve changed, so the type of irradiation defects varies significantly, and the defects of larger size were occurred.