Abstract

A control rod alloy composed of silver (Ag), indium (In), and cadmium (Cd) was heated in argon or oxygen at 1073 to 1673 K for 60 to 3600 s. Then, the release behaviors of the elements were analyzed. The elemental release was quite limited below the liquefaction temperature. In argon, almost the entire Cd content was released within 3600 s at >1173 K and within 60 s at >1573 K while the released fractions of Ag and In were <3% and <8%, respectively. In oxygen, the release of Cd, which was quite small at temperatures lower than 1573 K, largely increased to ~30% to 50% at 1673 K for short periods. The releases of Ag and In were also small in oxygen under the analyzed conditions. The comparison with the experimental data suggests that conventional empirical release models may underestimate the Cd release at lower temperatures just after control rod failure in severe accidents.

摘要

由银 (Ag)、铟 (In) 和镉 (Cd) 组成的控制棒合金在 1073 至 1673 K 的氩气或氧气中加热 60 至 3600 秒。然后，分析了元素的释放行为。元素释放在液化温度以下非常有限。在氩气中，几乎所有的 Cd 含量在 3600 秒内在 >1173 K 和 60 秒内在 >1573 K 时释放，而 Ag 和 In 的释放分数分别为 <3% 和 <8%。在氧气中，Cd 的释放量在低于 1573 K 的温度下非常小，但在 1673 K 的短时间内大幅增加至约 30% 至 50%。在分析条件下，Ag 和 In 在氧气中的释放量也很小。