Abstract Understanding of hydrogen isotope behaviors in plasma-facing wall is important from viewpoints of fuel control and tritium safety. Tungsten (W) is a candidate material of plasma-facing components. In this study, hydrogen diffusion coefficient and hydrogen solubility constant in the W deposition layer formed by hydrogen plasma sputtering were obtained by gas-driven permeation experiments. The hydrogen diffusion coefficient in the W deposition layer was smaller than that in bulk W, and the hydrogen solubility constant was larger than that in bulk W. Then, hydrogen permeation behavior through the W deposition layer growing on nickel plate by hydrogen plasma sputtering was observed in the temperature range from 77 to 145 °C. Initially, the hydrogen permeation flux steeply increased but then gradually decreased with increasing the thickness of the deposition layer. From the analysis of the permeation behavior by TMAP code, the recombination coefficient on the surface of the deposition layer was evaluated. The obtained recombination coefficient was smaller than that on bulk W.

中文翻译：

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通过钨沉积层的氢渗透行为

摘要 从燃料控制和氚安全的角度来看，了解面向等离子体壁的氢同位素行为很重要。钨 (W) 是面向等离子体组件的候选材料。在本研究中，通过气体驱动渗透实验获得了氢等离子体溅射形成的 W 沉积层中的氢扩散系数和氢溶解度常数。W沉积层中的氢扩散系数小于块体W中的氢扩散系数，氢溶解常数大于块体W中的氢溶解常数。然后观察氢通过等离子体溅射在镍板上生长的W沉积层的氢渗透行为在 77 至 145 °C 的温度范围内。原来，随着沉积层厚度的增加，氢渗透通量急剧增加，但随后逐渐减少。通过 TMAP 代码对渗透行为的分析，评估了沉积层表面的复合系数。获得的复合系数小于块体 W 上的复合系数。