空心铝挤压型材氧化色差带成因分析及对策  

Analysis and solution for anodizing streak on hollow aluminum extrusion profile

作　　者：辛荣 卢永红 唐宗元 孙娜 李政龙 袁圣 Xin Rong;Lu Yonghong;Tang Zongyuan;Sun Na;Li Zhenglong;Yuan Sheng(Southwest Aluminium(Group)Co.,Ltd.,Chongqing 401326,China)

机构地区：[1]西南铝业(集团)有限责任公司,重庆401326

出　　处：《铝加工》2023年第1期30-33,共4页Aluminium Fabrication

摘　　要：通过金相测试、SEM及EDS分析、硬度测试、电导率测试及自腐蚀电位测试对空心挤压铝合金型材阳极氧化色差带成因进行了分析。根据分析结果得出:氧化色差带主要是因挤压在线淬火不均匀,导致同一面上型材组织不均匀造成的。通过光学显微镜观察发现色差带与正常位置组织差异大:正常位置晶界清晰可见,色差带处晶粒内部分布着大量黑褐色弥散物,色差带位置的硬度、抗拉强度较正常位置分别低32 HV、65 MPa,屈服强度不合格,比正常位置低87 MPa。电导率趋势与力学性能趋势相反,色差带位置和正常位置的自腐蚀电位存在差异,导致阳极氧化出现差异性。Metallographic, SEM and EDS, hardness, electric conductivity and self-corrosion potential test were used to analysis the causes of anodizing streaking of hollow extruded aluminum profiles. The analysis result shows the main reason of the streaking defect is that the on-line quenching was not uniform,which led to the inhomogeneous microstructure on the same side of the profile. The analysis of streak defect shows that there was a big difference between the streak and the normal position, the grain boundary of the normal position was clearly. A large number of black dispersions were distributed in the grains of streak area, the hardness and tensile strength at this position were 32 HV and 65 MPa lower than the normal position. The yield strength at the streak position was unqualified and 87 MPa lower than the normal position. The difference of self-corrosion potential caused the color difference of the anodizing.

关 键 词：空心铝型材 阳极氧化 色差带 自腐蚀电位 

分 类 号：TG379[金属学及工艺—金属压力加工] TG178.2