电流型氢渗透传感器研究

利用Devanathan-Stachurski电解池原理制造恒电解式与电池式电流型氢渗透传感器,用于监测氢在钢中的扩散速率及浓度.研究了镀镍时间、密封电解液对渗氢电流的影响,试验了以羟基氧化镍粉末作为阴极材料的电池型氢渗透传感器.实验结果表明:钢件表面镀镍5 min作为原子氢催化氧化的集氢面,经约5 h氧化后可以消除电镀渗氢的影响,使背景电流降至0.5 μA/cm~2以下;由聚乙烯醇和羧甲基纤维素钠按质量比4∶1混合,再与0.2 mol/L KOH溶液配制成非流动性的电解液作为密封胶,用于传感器内部电解液与工件镀镍面之间的密封,与单电解液的测量结果一致;在相同充氢条件下,恒电解式与电池式电流型氢渗透传感器测得的氢渗透曲线结果一致,与施加氧化电势的方式无关.

Research on the Amperometric Sensor of Hydrogen Permeation

Based on the principle of electrochemical hydrogen permeation presented by Devanathan-Stachurski, a potentiostatic electrolyte type and galvani-cell type hydrogen sensors have been developed to determine the permeation rate and the concentration of atomic hydrogen in steels. The effects of plating time and sealed electrolyte on the current of hydrogen permeation were investigated. The galvani-cell type hydrogen sensor using NiOOH powders as the cathodic material was tested. The results have shown that nickel film plated for 5 minutes on steel serves as the catalytic oxidation side of gathering atomic hydrogen. About 5 hours of oxidation treatment can eliminate the hydrogen induced by plating nickel,and the background current can be reduced to 0.5 μA/cm~2. Polyvinyl alcohol and sodium carboxymethyl cellulose were mixed by mass ratio of 4∶1 with 0.2 mol/L KOH solution to prepare the ropy electrolyte as a sealant between the internal electrolyte in the sensor and the surface of catalytic nickel, which agrees with the measurement results with single electrolyte sensor. Permeation curves under similar experiment conditions detected with potentiostatic electrolyte type sensor are consistent with those with galvani-cell type hydrogen.