Zr-1%Nb alloy is used as cladding material in pressurised water reactors (PWR). Diffusion of hydrogen in this material is one of the important input parameters required for simulating the kinetics of hydrogen embrittlement. For this purpose, one end of cut piece of Zr-1%Nb alloy clad tube of PWR was polished, electrochemically charged with hydrogen and then annealed at required temperatures and time. Hydrogen content was determined in cut pieces of clad tube in axial direction employing hot vacuum extraction quadrupole mass spectrometry (HVE-QMS) technique. From the hydrogen profile in axial direction, diffusion coefficient of hydrogen was estimated employing the solution of Fick’s second law of diffusion with semi-infinite system boundary conditions. Activation energy (E a ) for diffusion of hydrogen in Zr-1%Nb was calculated from the slope of the Arrhenius plot between Log D H and 1/T. The obtained D 0 and E a are well in the range of expectations based on the literature data in various Zr based materials by considering micro-constituents in these materials.

中文翻译：

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氢在压水堆复合材料中的扩散研究

Zr-1%Nb 合金用作压水反应堆 (PWR) 的包壳材料。氢在这种材料中的扩散是模拟氢脆动力学所需的重要输入参数之一。为此，对压水堆 Zr-1%Nb 合金复合管切割件的一端进行抛光，用氢气进行电化学充电，然后在所需的温度和时间下退火。采用热真空提取四极杆质谱 (HVE-QMS) 技术在轴向方向上测定复合管切片中的氢含量。从轴向的氢分布，利用半无限系统边界条件的菲克第二扩散定律的解来估计氢的扩散系数。氢在 Zr-1%Nb 中扩散的活化能 (E a ) 由 Log DH 和 1/T 之间的阿伦尼乌斯图的斜率计算。通过考虑这些材料中的微成分，获得的 D 0 和 E a 完全在基于各种 Zr 基材料的文献数据的预期范围内。