LaNi_5合金长期贮氚的老化效应

Long term aging effects of LaNi_5 tritide storage material

为探究金属氚化物老化效应的机理 ,利用一个装载氘氚老化了 2 14 0天的LaNi5床开展实验研究。LaNi5合金贮氘氚 2 14 0天后能将几乎所有的衰变3He保留在晶格内 ,从氘化物的解吸等温线中可以观察到显著的氚老化效应 :(1)等温解吸线右移 ;(2 )坪斜增加 ;(3)可逆容量减少 ;(4)被称为“渣”(heel)的深捕陷氢同位素的形成。实验发现 ,当衰变3He在 12 30K高温消除后 ,这些老化效应完全消失 ,这就为氚老化效应的氦致机理提供了一个直接的证据。

In order to investigate the mechanism about the effects of tritium aging on metal hydride, experiments were performed on some aged LaNi 5 materials which had been loaded with DT and stored at room temperature for 2140 days. Tritium aged LaNi 5 retains nearly all the decayed 3He within the bulk. The tritium aging effects were observed by determining the deuterium desorption isotherms in various states. These effects included (1) a right shift of the isotherms, (2) an increase in the plateau slope, (3) a reduction in the reversible storage capacity, and (4) the formation of tightly bound tritium, which was often referred to as the tritium heel. It was found that these effects were completely removed after the 3He had been removed by 1230K heating of the samples. This provides a direct evidence for the mechanism that tritium aging is caused by 3He.