燃料电池不锈钢双极板CrC薄膜表面改性研究

Research on surface modification of stainless steel bipolar plates for fuel cells by CrC films with different thickness

采用离子镀技术在质子交换膜燃料电池(PEMFC)用不锈钢双极板表面沉积了不同厚度的Cr C薄膜。测试结果显示,随着薄膜厚度增加:镀膜样品表面粗糙度降低使其接触电阻降低。同时,镀膜样品的耐蚀性能和耐久性提高,在模拟腐蚀环境中的腐蚀电流密度分别降低了1个数量级(阴极)和0.5个数量级(阳极);镀膜样品在腐蚀测试过程中溶解生成的铁离子数量减少,厚度较大的薄膜可以更有效地保护不锈钢基体免受腐蚀。

The CrC films with different thickness were deposited on stainless steel as bipolar plates for proton exchange membrane fuel cell （PEMFC） by arc ion plating （ALP）. The results show that as the thickness of the film increases, the surface roughness of the coated sample decreases which makes the ICRs of the coated sample decrease. Also, the corrosion resistance and durability of the coated sample are enhanced. The corrosion current density of the coated sample decreases by 1 order of magnitude （cathodic） and 0.5 orders of magnitude （anodic） in the simulated corrosive environment respectively. Moreover, the amount of Fe ions dissolved from the coated sample during the corrosion testing decreases. The film with larger thickness can more effectively protect the stainless steel substrate from corrosion.