摘要
以304不锈钢为基材,Ti-45Al-8Nb金属间化合物为电极,制备电火花沉积涂层,并研究其在锌液中的腐蚀行为。结果表明,涂层与基体呈冶金结合,是电极材料与基体材料剧烈重熔扩散的产物。相比304不锈钢,涂层样品的耐熔锌腐蚀性能显著提升,表现为孕育型腐蚀,孕育期为15天。涂层的腐蚀最初发生于样品的棱角处,属于典型的裂纹-瓦解机制。涂层碎片与锌液发生少量元素扩散,生成富Fe、Al的腐蚀产物。依据润湿的相关理论,讨论了涂层中原生裂纹对涂层耐熔锌腐蚀性能的影响。如果适当改善沉积工艺,减少涂层裂纹,有望延长涂层的使用寿命。
Ti-45A1-8Nb coating was prepared on the surface of 304 stainless steel by electrospark deposition （ESD）. Corrosion resistance of the coating in mohen zinc was investigated. Experiment results show that metallurgical bond between the coating and substrate is realized. The coating exhibits 15 d incubation period without any corrosion in molten zinc. Initial corrosion occurs at edges and corners of the coating specimen and follows the crack-fracture mechanism. Corrosion products rich in Fe and A1 are produced via the elements diffusion between the coating and molten zinc. The effect of primary cracks on the molten zinc corrosion resistance of the ESD coating was discussed. Decreasing primary cracks by improving technique of ESD, molten zinc corrosion resistance of the coating could be enhanced.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2014年第2期151-156,共6页
Transactions of Materials and Heat Treatment
基金
国家"973"计划(2011CB605500)
新金属材料国家重点实验室自主研究课题(2012Z06)
