LaCrO3-based coatings deposited by high-energy micro-arc alloying process on a ferritic stainless steel interconnect material
LaCrO3-based coatings deposited by high-energy micro-arc alloying process on a ferritic stainless steel interconnect material
复制标题
采用高能微弧合金化工艺在铁素体不锈钢互连材料上沉积的 LaCrO3 基涂层
DOI：
10.1016/j.jpowsour.2010.01.023
复制
发表时间：
2010-07-01
影响因子：
9.2
通讯作者：
Zeng, C. L.
中科院分区：
文献类型：
--
作者：
Feng, Z. J.;Zeng, C. L.
由于铬挥发性、正极材料中毒、电导率迅速下降和抗氧化性低，目前使用的铁素体不锈钢互连不适合在中等温度下工作的固体氧化物燃料电池中实际应用。为了克服这些问题，提出了一种新颖、简单、经济的高能微弧合金化（HEMAA）工艺，用于制备430型不锈钢互连层的lacro3基涂层。然而，由于氧化电极的高脆性，用HEMAA沉积氧化物涂层比金属涂层要困难得多。因此，首先使用Cr电极棒通过HEMAA在合金表面获得Cr合金化层，然后使用lacro3 - 20wt .%Ni的电极棒获得lacro3基涂层，涂层与基体之间发生冶金结合。850℃空气初步氧化试验表明，LaCrO3基镀层呈现三层组织，外层为NiFe2O4，亚层为较厚的LaCrO3亚层，内层为较薄的富cr2o3，对基体合金具有良好的保护作用，接触电阻较低。(C) 2010 Elsevier B.V.版权所有
Currently used ferritic stainless steel interconnects are unsuitable for practical applications in solid oxide fuel cells operated at intermediate temperatures due to chromium volatility, poisoning of the cathode material, rapidly decreasing electrical conductivity and a low oxidation resistance. To overcome these problems, a novel, simple and cost-effective high-energy micro-arc alloying (HEMAA) process is proposed to prepare LaCrO3-based coatings for the type 430 stainless steel interconnects. However, it is much difficult to deposit an oxide coating by HEMAA than a metallic coating due to the high brittleness of oxide electrodes for deposition. Therefore, a Cr-alloying layer is firstly obtained on the alloy surface by HEMAA using a Cr electrode rod, followed by a LaCrO3-based coating using an electrode rod of LaCrO3-20 wt.%Ni, with a metallurgical bonding between the coating and the substrate. The preliminary oxidation tests at 850 degrees C in air indicate that the LaCrO3-based coatings showed a three-layered microstructure with a NiFe2O4 outer layer, a thick LaCrO3 sub-layer and a thin Cr2O3-rich inner layer, which thereby possesses an excellent protectiveness to the substrate alloy and a low electrical contact resistance. (C) 2010 Elsevier B.V. All rights reserved.