Observation of Tritium Distribution in Pure Vanadium and V-5 mol%Fe Alloy by Tritium Radioluminography
Observation of Tritium Distribution in Pure Vanadium and V-5 mol%Fe Alloy by Tritium Radioluminography
复制标题
氚放射发光观察纯钒和V-5摩尔合金中氚的分布
DOI：
10.13182/fst02-a22647
复制
发表时间：
2002
影响因子：
0.9
通讯作者：
T. Ohnishi
中科院分区：
文献类型：
--
作者：
H. Saitoh;H. Homma;Y. Noya;T. Ohnishi
本文应用氚放射发光法对纯钒和V-5mol%Fe合金进行了氚的放射发光分析，观察了氚在两种合金中的分布情况，并对两种合金中的局部氚浓度进行了评价。结果表明，该方法能定量、直观地显示样品中某一微观区域的氚分布。在纯钒试样中，局部氚浓度根据晶粒的晶体取向而相差约三倍。（001）和（111）取向的颗粒的氚放射性分别为1Bq/mm ~ 2和0.4Bq/mm ~ 2。这些值对应于15 mol ppb和6 mol ppb的氚浓度。局部氚浓度的差异归因于沉淀氢化物的形态取决于晶粒的晶体取向的变化。对于成像板中记录的放射性，样品中氚产生的X射线成分仅为2%，即，大部分强度归因于β射线。在V-Fe合金试样中，氚的分布与电弧熔炼后凝固过程中形成的铁偏析有关。截面观测表明，平衡分布中的局部氚浓度取决于试样中局部铁浓度。当铁偏析区的铁浓度从3mol%增加到4.5mol%时，局部氚浓度从115 molppb逐渐降低到70 molppb。
ABSTRACT Tritium radioluminography was applied to pure vanadium and V-5 mol%Fe alloy to observe the tritium distribution and to evaluate the local tritium concentration in them. It was demonstrated that the tritium distribution at a microscopic area in the specimens was quantitatively and graphically displayed. In the pure vanadium specimen, the local tritium concentration was about three times different depending on the crystal orientation of the grains. The tritium radioactivity of the grains with (001) and (111) orientation are 1 Bq/mm2 and 0.4 Bq/mm2, respectively. These values correspond to the tritium concentration of 15 mol ppb and 6 mol ppb. The difference of the local tritium concentration was attributed to the variety of the morphology of precipitated hydride depending on the crystal orientation of the grains. For the radioactivity recorded in the imaging plate, the component of the X-rays generated from tritium in the specimen was only 2%, i.e., most of the intensity was attributed to the β-rays. In the V-Fe alloy specimen, it was shown that the tritium distribution correlates with iron segregation formed during solidification after the arc melting. The cross sectional observation showed that the local tritium concentration in equilibrium distribution depends on the local iron concentration in the specimen. The local tritium concentration gradually decreases from 115 mol ppb to 70 mol ppb as the iron concentration at the iron segregated region increases from 3 mol% to 4.5 mol%.