摘要
铁素体不锈钢的热膨胀系数与固体氧化物燃料电池(SOFC)的组元相近,成本低廉,具有良好的抗氧化性,已被广泛用作SOFC电池堆的金属连接体材料.但是表面Cr2O3膜的挥发会导致SOFC阴极Cr中毒,缩短SOFC的服役寿命.为解决这一问题,本文利用电镀的方法在铁素体不锈钢(SUS 430)连接体表面沉积CuMn3O4复合涂层,研究了复合电镀Cu-Mn3O4涂层的电镀工艺,结果表明:复合电镀的适宜工艺参数为:溶液pH值为3,阴极电流密度为2.12 A/dm2,镀液温度为35℃,溶液中Mn3O4粉末添加量为20 g/L.并研究了涂覆不锈钢在800℃空气中的氧化行为及氧化膜的导电性能.涂覆Cu-Mn3O4不锈钢氧化后表面生成CuO、(Mn,Cu)3O4和(Fe,Cu)3O4尖晶石氧化物,表面氧化物的导电性良好,并能有效阻止Cr向外迁移和扩散.
Ferritic stainless steel has been widely applied to the metallic interconnect materials of solid oxide fuel cell （SOFC） due to its good coefficient of thermal expansion （CTE） matching with other components of SOFC, low cost as well as excellent oxidation resistance. However, volatilization of Cr2 03 on the surface could cause SOFC cathode Cr poisoning and then shorten the service time of SOFC. In order to solve this problem, Cu - Mn304 composite coatings were deposited on the ferritic stainless steel （ SUS 430） by electroplating method, and electroplating technological conditions were investigated in this work. The suitable electroplating parameters, such as pH was 3, cathode current density was 2. 12 A/din2 , bath temperature was 35 ℃ and the concentration of Mn3 04 particles was 20 g/L, were determined. In addition, the oxidation behavior of the coated stainless steel at 800 ℃ in air and the conductivity of oxide scale were also studied, It was found that the oxide scale formed on the coated steel was consisted of CuO, （Mn, Cu）304 and （Fe, Cu）304 spinel. The Cr- free surface scale showed a high electrical conductivity and it effectively suppressed Cr migration and diffusion.
出处
《材料与冶金学报》
CAS
北大核心
2014年第2期138-145,156,共9页
Journal of Materials and Metallurgy
基金
国家自然科学基金项目(51371048)
