7075铝合金厚板硫酸阳极氧化后色差原因分析  

Reason analysis of color difference of 7075 aluminum alloy thick plate after sulfuric acid anodizing

作　　者：寻坚 杨雷 刘美玲 董晓宇 任天琪 黎正华 曹潇嵘 周亮 Xun Jian;Yang Lei;Liu Meiling;Dong Xiaoyu;Ren Tianqi;Li Zhenghua;Cao Xiaorong;Zhou Liang(Hunan Aerospace Institute of Electromechanical Device&Special Materials,Changsha Hunan 410205,China;Hunan Aerospace Chengyuan Precise Machinery Co.,Ltd.,Changsha Hunan 410205,China)

机构地区：[1]湖南航天机电设备与特种材料研究所,湖南长沙410205 [2]湖南航天诚远精密机械有限公司,湖南长沙410205

出　　处：《金属热处理》2024年第12期295-300,共6页Heat Treatment of Metals

摘　　要：为解决7075铝合金厚板硫酸阳极氧化后产生色差的问题,采用光学显微镜、扫描电镜、室温拉伸试验等方法对颜色不同部位的组织和性能进行了表征。结果表明,冷却速度是7075铝合金厚板硫酸阳极氧化膜层色差产生的主要原因。固溶时达不到所需冷却速度的部位,产生大量微米级η相,在硫酸阳极氧化时膜层形成不均匀,导致外观呈现灰黑色;固溶时达到所需冷却速度的部位,显微组织以纳米级η′亚稳析出相为主,硫酸阳极氧化时膜层均匀,颜色正常为灰白色;硫酸阳极氧化后发黑部位经过重新热处理调控组织后,膜层颜色恢复为正常灰白色。In order to solve the problem of color difference caused by sulfuric acid anodizing of the 7075 aluminum alloy thick plate,optical microscope,scanning electron microscope,room temperature tensile testing and other methods were used to study the microstructure and properties of different color parts.The results show that the cooling rate is the main reason for the color difference of the sulfuric acid anodized film layer of the 7075 aluminum alloy thick plate.In the parts that can not reach the required cooling rate during solution treatment,a large number of micron-sizedηphases are generated,and the film layer is formed unevenly during the sulfuric acid anodizing,resulting in a gray-black appearance.In the parts that can reach the required cooling rate during solution treatment,the microstructure is dominated by nano-scaleη′metastable precipitated phase,and the film layer is uniform during sulfuric acid anodizing,and the color is normally gray white.The gray-black part after sulfuric acid anodizing is re-heat-treated to regulate the microstructure,ant then the color of the film layer is returned to normal gray white.

关 键 词：7075铝合金 硫酸阳极氧化 固溶时效处理 色差 

分 类 号：TG146.21[一般工业技术—材料科学与工程]