• 作者： Wu, Jiann-Kuo
• 中文摘要： 本文利用電化學法在 278-303K 測量氫氣對純鐵之擴散與滲透係數。本法所測得之陽極電流即是滲透電流(ip), 最終穩定狀態之氫流量與充電電流之平方成線性關係。氫氣釋放及進入鐵之機理也確證為連鎖放電-化學脫離作用。定電流下之氫滲透所需之活化能是17.7 KJ/mol; 相當於定氫氣壓力下之氫滲透活化能是 36.6 KJ/ mol, 後者與高溫氣相測值符合。總之, 氣相法與電化學法所測出之滲透係數是無法相比較的, 因為氣相法所測出滲透量是與氣壓之平方根成正比, 而陰極充氫滲透量是與電流平方根成正比。此法所測得之室溫擴散係數也較氣相法所測值大。
• 英文摘要： Temperature dependent electrochemical measurement of diffusivity and permeability of hydrogen through VP iron was obtained between 278-303 K. The measured anodic or permeation current, i/sub p/, is proportional to unsteady or steady state hydrogen flux on the output side of the membrane. Steady state flux, is linearly related to (current)/sup 1/2/. The mechanism of hydrogen evolution and entry into iron involves coupled discharge-chemical desorption. The activation energy for permeation in VP iron when measured at constant current is 17.7 kJ/mol. The activation energy for permeation at constant fugacity is 36.6kJ/mol. The latter is in good agreement with the value obtained by extrapolating higher temperature gas phase data to near room temperature. Gas phase and electrochemical permeation measurement are not directly comparable because gas phase permeation is proportional to (fugacity)/sup 1/2/whereas cathodic charge permeation is proportional to (current)/sup 1/2/. Measured diffusivity at room temperature is higher than the value extrapolated from higher temperature gas phase permeation.
• 中文關鍵字： 電化學滲透法; 滲透性; 擴散係數; 氫溶解度; 純鐵
• 英文關鍵字： Electrochemical Permeation Technique; Permeability; Diffusivity; Hydrogen Solubility; Pure Iron