摘要
在多聚磷酸钠和三氧化铬组成的电解液体系中,采用微弧氧化方法在LY12铝合金表面制备黑色陶瓷膜.结果表明:随反应时间的延长,膜层颜色由浅至深最后形成均匀的黑色,厚度逐渐增加且趋于缓慢,硬度增大;膜层由致密层和疏松层构成,表面残留大量未完全封闭的放电通道;膜层由大量的α-Al_2O_3及少量的γ-Al_2O_3组成,而在单一的多聚磷酸钠电解液中,膜层由γ-Al_2O_3组成,三氧化铬能促进γ-Al_2O_3向α-Al_2O_3转化和黑色膜层的形成.随三氧化铬浓度的增加,膜层磨损率上升后略有下降,摩擦系数下降后略有上升;随载荷和转数的增加,膜层磨损率升高,摩擦系数减少.
In the electrolyte system sodium polyphosphate and chromic anhydride,the black ceramic coating was prepared on the LY12 aluminum by micro-arc oxidation. Results showed that with the increase of reaction time,the color of coating became darker and darker,and finally changed into uniform black. The coating thickness was increased gradually and slowly while the coating hardness was improved. The coating was composed of compact inner layer and porous layer,and lots of residual unclosed charging channels emerged on the surface.The coating was composed of a large amount of α-Al_2O_3 and a little γ-Al_2O_3. But in the single sodium polyphosphate electrolyte,the coating was only composed of γ-Al_2O_3. Therefore,chromic anhydride promoted the transformation from γ-Al_2O_3 into α-Al_2O_3,and the formation of black coating. As the concentration of chromic anhydride increased,the wear rate of the coating increased firstly and then decreased,while the friction factor decreased firstly and then increased slightly. Besides,with the increases of load and revolution,the wear rate of coating was improved and the friction factor was reduced.
出处
《白城师范学院学报》
2016年第11期1-6,共6页
Journal of Baicheng Normal University
基金
吉林省科技厅项目(20100546)
吉林省2015年大学生创新创业项目"镁合金陶瓷涂层的制备工艺及耐腐蚀性"
关键词
铝合金
微弧氧化
陶瓷膜
摩擦磨损
三氧化铬
LY12 aluminum alloy
micro-arc oxidation
ceramic coating
friction and wear
chromic anhydride
