摘要
针对2219铝合金瓜瓣零件经硫酸阳极氧化处理后表面出现黑点的问题,通过扫描电子显微镜、体视显微镜、金相显微镜、X射线能谱仪等手段,分析了黑点出现的原因。研究结果表明:2219铝合金中呈块状偏析聚集的第二相金属间化合物在碱腐蚀和阳极氧化过程中由于电化学特性和氧化溶解而发生完全脱落或部分脱落后形成凹坑,该部位的反光性与正常区域存在差异而表现为黑点缺陷。黑点区域存在阳极氧化膜层,且膜层的耐腐蚀性能满足使用要求。预先对2219铝合金瓜瓣零件进行二次热处理(淬火+人工时效)可消除阳极氧化膜表面的黑点现象。
the causes for the formation of black spots on the surface of 2219 aluminum alloy melon petal part after anodization in sulfuric acid were analyzed by scanning electron microscopy,stereomicroscopy,metallographic microscopy,and energy-dispersive X-ray spectroscopy.The results indicated that the blocky intermetallic compounds segregated and aggregated as second phases in the 2219 aluminum alloy completely or partially detach from the matrix during alkaline etching and anodic oxidation due to their electrochemical characteristics and oxidation dissolution.The pits formed therefore are different from the normal area in reflectivity,and the black spots appear.There exists an anodic oxide film in the black spot area,whose corrosion resistance even meets the application requirement.The black spot defects of anodic oxide film on the 2219 aluminum alloy melon petal part can be eliminated by secondary heat treatment i.e.quenching and artificial aging prior to anodization.
作者
林少凯
杨娇
袁国崇
周洁
朱小玲
唐春
许璐迪
陈伟
LIN Shaokai;YANG Jiao;YUAN Guochong;ZHOU Jie;ZHU Xiaoling;TANG Chun;XU Ludi;CHEN Wei(Sichuan Aerospace-Changzheng Equipment Manufacturing Co.,Ltd.,Chengdu 610100,China)
出处
《电镀与涂饰》
CAS
北大核心
2023年第12期11-16,共6页
Electroplating & Finishing
关键词
铝−铜−锰合金
硫酸阳极氧化
黑点缺陷
二次热处理
金属间化合物
偏析
故障处理
aluminum–copper–manganese alloy
sulfuric acid anodization
black spot defect
secondary heat treatment
intermetallic compound
segregation
troubleshooting
