熔铸法制备Al_2O_3/金属复合涂层微观组织的研究  

Research on microstructure of alumina/metal coating prepared by melting-casting

作　　者：薛小锋[1] 王泽华[1] 周泽华[1] 邵佳[1] 

机构地区：[1]河海大学力学与材料学院,江苏南京210098

出　　处：《粉末冶金工业》2015年第2期39-45,共7页Powder Metallurgy Industry

基　　金：中国教育部专项资金资助项目(625010312);江苏省普通高校研究生科研创新计划资助项目(CXZZ13_0245)

摘　　要：采用Fe2O3+Cr2O3+Al和Ni O+Al双层预涂覆结构,利用自蔓延熔铸法在碳钢基体上制备Al2O3/金属复合涂层,研究涂层与基体结合界面处的微观形貌、结合状态、涂层组织以及元素的分布。结果表明:涂层由α-Al2O3、FeNi、Cr、Al Ni3、Fe-Cr组成;复合涂层与基体紧密结合,无明显的缝隙或者孔洞存在,在界面处存在明显的元素扩散;涂层中主要有等轴晶、柱状晶、树枝晶以及板条状组织,各元素在界面处分布较均匀,但在涂层中部,金属元素发生了偏聚;延长保温时间,金属元素的偏聚程度加剧。A sort of alumina/metal coating characterized by a bi-layered structure of Fe2O3＋Cr2O3＋Al plus Ni O＋Al layers, was successfully prepared on steel substrate by melting-casting technique. The microstructure, bonding status of the interface between the coating and the substrate, and the element distribution of the coating were studied. Results indicate that the coating is composed of α-Al2O3, Fe-Ni, Cr, Al Ni3 and Fe-Cr. There is an excellent bonding between the coating and the substrate, and no hole or gap is found in the composite. Moreover, there is obvious element diffusion in the interface. The coating is composed of equiaxed grain, columnar grain, dendrites and lath phase. The elements present a uniform distribution in the interface but an obvious segregation in the middle of the coating. The segregation degree of metal elements is strengthened when extending the holding time.

关 键 词：熔铸法 Al2O3/金属复合涂层 微观形貌 元素分布 

分 类 号：TB306[一般工业技术—材料科学与工程]