镁合金微弧氧化膜/基界面显微组织研究  

Boundary microstructure between matrix and dense inner layer formed on magnesium alloys by micro-arc oxidation

作　　者：陈显明[1,2] 潘青林[2] 

机构地区：[1]肇庆学院电子信息与机电工程学院,广东肇庆526061 [2]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《兵器材料科学与工程》2015年第1期50-54,共5页Ordnance Material Science and Engineering

基　　金：中南大学博士后基金资助项目(126226);广东省科技计划资助项目(2012B011000038)

摘　　要：为研究镁合金微弧氧化膜层的膜/基界面区附近的组织形态,在碱性电解液中,以AZ91镁合金为基体制备出微弧氧化陶瓷薄膜。采用恒电流控制模式,电流密度为10~30 A/dm2;利用透射电镜（TEM）和扫描电镜（SEM）研究了氧化薄膜界面及附近的显微结构。研究表明：微弧氧化膜层的膜/基界面区附近的组织以微晶和纳米晶为主;氧化膜层膜/基界面区附近的显微硬度比基体有大幅度提高,这主要是由于膜/基界面区附近形成了Mg和Mg O的互相渗透区域,同时Mg和Mg O的晶粒都非常细小,具有细晶强化的效果。The boundary microstructure between matrix and dense inner sublayers of the ceramic coating formed on AZ91 magnesium alloy substrate by micro- arc oxidation（MAO）was studies. The coating was prepared in an alkaline electrolytic solution,employing constant-current controlled AC power supply with current density of 10 to 30 A/dm2. The microstructure of the coatings was characterized using transmission electron microscopy（TEM）and scanning electron microscopy（SEM）. It is found that the main constituent of coating adjacent to boundary is microcrystalline and nanocrystalline. The microhardness of coating adjacent to boundary is higher than that of matrix due to the formation of intermixing of Mg and Mg O and their refined grains,leading to fine-crystal strengthening.

关 键 词：镁合金 微弧氧化 界面 微晶 膜层 性能 

分 类 号：TG146[一般工业技术—材料科学与工程]