等离子喷涂Al_2O_3涂层的介电性能  

Dielectric properties for plasma sprayed alumina coating

作　　者：曾威[1] 邓春明[1] 刘敏[1] 邓畅光[1] 朱晖朝[1] 

机构地区：[1]广东省工业技术研究院(广州有色金属研究院),广东广州510650

出　　处：《材料研究与应用》2011年第4期275-278,共4页Materials Research and Application

摘　　要：采用大气等离子喷涂制备厚度大于1.0mm的氧化铝涂层,分别对涂层的显微结构、相组成及氧化铝涂层的介电性能进行了表征,并对氧化铝涂层的击穿失效机理进行了探讨.结果表明,等离子喷涂氧化铝涂层为层状结构,以多孔的γ-Al2O3为主晶相,其体积电阻率、击穿电压均明显低于烧结氧化铝块材,涂层的介电失效是由电晕放电击穿和热击穿共同作用而致.Microstructure, phase composition and dielectric property of the air plasma sprayed alumina coating with a coating thickness over 1.0 mm were characterized, and the breakdown failure mechanism of alumina coating was discussed. The results show that the plasma sprayed alumina coating, with γ-Al2O3 as the predominant crystal phase, presents laminar microstructure, and its volume resistivity and breakdown voltage are far lower than those of the bulk alumina sintered. And the dielectric failure of plasma sprayed alumina coating is caused by both corona discharge breakdown and thermal breakdown.

关 键 词：大气等离子喷涂 氧化铝涂层 介电性能 

分 类 号：TF123.1[冶金工程—粉末冶金]