铝锂合金微弧氧化陶瓷膜层特性的研究  

Properties Research of Ceramic Coating on Al-Li Alloy by Micro-arc Oxidation

作　　者：刘一洋[1] 赵志龙[1] 阎光明[1] 侯军占[1] 

机构地区：[1]西北工业大学机电学院,陕西西安710072

出　　处：《电镀与环保》2007年第2期25-27,共3页Electroplating & Pollution Control

摘　　要：采用先恒流、后恒压的微弧氧化方法,在铝锂合金(添加微量稀土元素Ce)表面制备陶瓷化膜层。研究了氧化时间和脉冲频率对膜层生长过程和表面形貌的影响。结果表明:膜层厚度随着反应时间的延长而增加,在更高频率的高能脉冲作用下(>600 Hz)生长速率更快;膜层表面多孔、起伏不平,延长反应时间或提高脉冲频率会导致烧蚀留下的坑洞变大,表面粗糙度亦随之增大;膜层与基体结合良好,由内部致密层和外部疏松层组成,总厚度可达50μm;EDS分析表明,膜层由Al、O、Si构成,Si元素的摄入认为是NaOH-Na2SiO3电解液体系中的SiO32-参与反应进入膜层。A ceramic coating is prepared by micro-are oxidation in a controlled mode of constant-current-earlier-constant-voltage-later on Al-Li alloy in an electrolyte containing NaOH and Na2SiO3. The growth process and microstructure variation of micro-are oxidation coating are investigated. The results show that the thickness of coating is growing while the growth rate is gradually decreasing during the process. The coating grows more rapidly under higher frequency（ 〉 600 Hz） by DC pulse .The thickness of the MAO film is about 50 μm and the coating is porous and uneven. The fabricated ceramic coating is combined well to the Al substrate. The results also show that ceramic coating is composed of two-layer structure with outer loose zone and inner compact zone. The coating is mainly made of Al,O and Si. The existence of Si implies that the elemental component in an electrolyte is compounded into the coating by MAO.

关 键 词：2090铝锂合金 微弧氧化 高能脉冲 膜层生长 

分 类 号：TG174.45[金属学及工艺—金属表面处理]