TA2钛板掺杂钒离子渗碳层的耐腐蚀性能

为提高钛基双极板的耐腐蚀性能和导电性，在TA2纯钛的表面进行双辉离子渗碳，另外为降低渗碳温度，在渗碳过程中掺杂钒。使用扫描电镜和能谱分析、X射线衍射对改性层的组织结构、化学成分、物相组成进行研究，并测得改性层的界面接触电阻率、耐腐蚀性能。结果表明，在优化的制备工艺参数下，在TA2表面生成结构致密的TiC改性层、钒掺杂渗碳改性层。当压实力为140 N/cm²时，730℃下制备的钒掺杂渗碳改性层、850℃下制备的TiC改性层、TA2基体的界面接触电阻率分别是1.17、3.66、14.71 mΩ/cm²。在模拟双极板的工作环境中，测得730℃下制备的钒掺杂渗碳改性层、850℃下制备的TiC改性层的自腐蚀电流密度分别是5.238、7.563μA/cm²,均比TA2基体的腐蚀电流密度低1个数量级。在离子渗碳的过程中掺杂钒可以有效降低渗碳的工艺温度，并且提高TA2基体的导电性和耐腐蚀性能。

Corrosion resistance of vanadium doping ion carburized layer of TA2 titanium plates

In order to improve corrosion resistance and electrical conductivity of titanium-based bipolar plate, the surface of TA2 pure titanium was treated by double glow ion carburizing, and vanadium was doped in the carburizing process to reduce the carburizing temperature. The structure, chemical composition and phase composition of the modified layer were characterized by scanning electron microscopy, energy dispersive analysis and X-ray diffraction. The interface contact resistance and corrosion resistance of the modified layer were measured. The results show that under the optimized preparation process parameters, dense TiC modified layer and vanadium-doped carburizing modified layer are formed on the surface of TA2. When the compaction force is 140 N/cm², the interface contact resistivities of the vanadium-doped carburizing modified layer prepared at 730 ℃, TiC modified layer prepared at 850 ℃ and TA2 matrix are 1.17, 3.66 and 14.71 mΩ/cm². The self corrosion current densities of the vanadium-doped carburizing modified layer prepared at 730 ℃ and TiC modified layer prepared at 850 ℃ under the simulated bipolar plate working environment are 5.238 and 7.563 μA/cm², respectively, which are 1 order of magnitude lower than that of TA2 substrate. Doping vanadium in the process of ion carburizing can effectively reduce the process temperature of carburizing and improve the conductivity and corrosion resistance of TA2 matrix.