多弧離子鍍TiN膜的腐蝕行為
(武漢理工大學(xué) 材料復(fù)合新技術(shù)國家重點實驗室，武漢430070)
摘 要: 為了增強鈦金屬雙極板的耐腐蝕性能，通過多弧離子鍍膜技術(shù)在鈦基雙極板表面鍍一層TiN，對薄膜的表面形貌，晶體結(jié)構(gòu)與耐腐蝕性能之間的關(guān)系進(jìn)行研究。結(jié)果表明：鍍有TiN膜樣品的耐腐蝕性能比未鍍膜樣品的有明顯提高，其腐蝕電流密度最低可達(dá)201 μA/cm2。測試其動電位極化曲線和恒電位極化曲線發(fā)現(xiàn)，樣品的耐腐蝕性能與薄膜的晶體結(jié)構(gòu)以及表面顆粒和孔洞有密切的關(guān)系。適當(dāng)?shù)木w擇優(yōu)取向有利于提高樣品的耐腐蝕性能，而表面的顆粒和孔洞對樣品的長期耐腐蝕性有很大影響。通過能譜分析發(fā)現(xiàn)，腐蝕后的樣品表面發(fā)生了氧化。
關(guān)鍵字: 質(zhì)子交換膜燃料電池；鈦基雙極板；多弧離子鍍；耐腐蝕性；TiN膜
PEMFC by multi-arc ion plating
（State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,
Wuhan University of Technology, Wuhan 430070, China）
Abstract:In order to enhance the corrosion resistance of Ti bipolar plates, TiN films were deposited on titanium as bipolar plates for proton exchange membrane fuel cells (PEMFC) by adjusting the nitrogen pressure. The relationships among the surface morphology, crystal structure and corrosion resistance of the film were investigated. The results show that the TiN-coated titanium exhibits higher corrosion resistance than uncoated titanium, the lowest current density was 201 μA/cm2. Potentiodynamic and potentiostatic tests show that the corrosion resistance of TiN-coated sample is greatly associated with the crystal structure and particles and holes on the surface of the film. The suitable growth orientation is favorable to enhancing the corrosion resistance of TiN-coated samples. However, the particles and holes on the surface are bad for the long-time corrosion resistance of the sample. The energy dispersive spectroscopy (EDS) shows that the surface oxidation occurs on the surface of the sample after corrosion.
Key words: PEMFC; titanium bipolar plates; multi-arc ion plating; corrosion resistance; TiN film
