Tritium Inventory in Fuel Element of Light Water Reactor and Release Mechanism of Tritium to Reactor Coolant

对铀三元裂变产生的氚向反应堆冷却剂释放的机理进行了实验研究。特别考虑了以下三个基本过程的影响；(1)通过氚和锆蛋白热迁移实验，考察了热梯度对氚在锆包层中扩散的影响。(2)在锆合金高温蒸汽氧化实验的基础上，考察了氚与包层材料高温高压冷却水氧化生成的protium扩散的相互作用，定量考察了水还原生成氢的溶解机理。(3)为考察锆中溶解氧对氚扩散的影响，提出了一种新型的氢同位素扩散系数的实验测量方法，该方法是利用氢气的辉光放电将氢同位素注入试样表面。

The release mechanisms of tritium produced by ternary fission of uranium to reactor coolant were experimentally examined. In particular, the influences of following three elementary processes were considered; (1)Influence of thermal gradient upon the diffusion of tritium in the zircaloy cladding was examined by carrying out the thermo-migration experiment of tritium and protiumin zirconium. (2)Interaction of tritium diffusion with that of protium originated from the oxidation of cladding materials with high temperature and pressure cooling water was examined on the basis of the oxidation experiment of zircaloy with high temperature steam,in which dissolution mechanism of hydrogen originated from the reduction of water was quantitatively examined. (3)For examination of the influence of oxygen dissolved in zircaloy upon the diffusion of tritium, a new type exeprimental method to measure the diffusion coefficient of hydrogen isotopes was developed, which is based on the implantation technique of hydrogen isotopes into the specimen surface by making use of glow-discharge of hydrogen gas.