铝合金零件阳极氧化表面局部发黑弊病分析  

Analysis of Dim Color with Dark Streaks Defect on Local Area of Anodized LF6M Aluminum Alloy Parts Surface

作　　者：张斌[1] 齐东栋[1] 黄硕[1] 胡小华[1] 

机构地区：[1]中国人民解放军驻三二○厂军事代表室,江西南昌330024

出　　处：《电镀与精饰》2010年第4期40-43,共4页Plating & Finishing

摘　　要：铝合金零件硫酸阳极氧化后表面出现发暗、发黑的非正常现象,影响产品质量和性能。采用扫描电子显微镜、金相分析等手段,经综合分析得出产生此弊病的主要原因是:包铝层厚度不均匀,在阳极氧化过程中合金基体被氧化,合金中的β相和Mg2Si相被优先溶解、(FeMn)Al6相不被氧化,使阳极氧化膜中出现夹杂和空洞所导致的。It was found some times that defects of dim color with dark streaks appeared on local area of LF6M aluminum alloy parts surface after anodizing in sulphuric acid solution. These defects affect quality and performance of the product. Main causes for occurring this phenomenon were analyzed with methods of SEM and metallography. Experimental results revealed that if the thickness of the protective AI coating on the LF6M alloy surface was not uniform and there existed area where the protective Al coating was too thin to protect the LF6M alloy substrate from corrosion during the anodizing process. Then, the LF6M alloy substrate would be corroded during the anodizing of the parts. The β phase and Mg2Si phase in the alloy substrate were dissolved preferentially while the （FeMn）Al6 phase was remained undissolution. Thus holes and inclusions would be left in the substrate surface layer to form the defects of dim color with dark streaks on local area of the anodized LF6M aluminum alloy part surface.

关 键 词：铝合金 金相组织 发黑 阳极氧化 

分 类 号：V434[航空宇航科学与技术—航空宇航推进理论与工程]