Mn微合金化Al-Si-Cu-Mg合金显微组织及耐蚀性能研究  

Effect of Mn on the Microstructure and Corrosion Resistance of Al-Si-Cu-Mg Alloys

作　　者：陈浩[1,2] 李天宇 王瑞[1,2] 王东涛[1,2] 张鸣鹤 赵新宇 施昊 蔡伟涛 长海博文 CHEN Hao;LI Tianyu;WANG Rui;WANG Dongtao;ZHANG Minghe;ZHAO Xinyu;SHI Hao;CAI Weitao;NAGAUMI Hiromi(High-Performance Metal Structural Materials Research Institute,Soochow University,Suzhou 215131,China;School of Iron and Steel,Soochow University,Suzhou 215137,China)

机构地区：[1]苏州大学高性能金属结构材料研究院,江苏苏州215131 [2]苏州大学沙钢钢铁学院,江苏苏州215137

出　　处：《铸造技术》2024年第5期452-458,共7页Foundry Technology

基　　金：国家重点实验室开放课题(32115007,2022RALKFKT008);苏州市基础研究计划项目(前沿技术研究)(SYG202324)。

摘　　要：Al-Si-Cu-Mg系列合金具有优异的强韧性,但其中的含Cu强化相极大地影响了该系合金的耐蚀性能。因此,本文通过对不同Mn含量的Al-7Si-2Cu-0.6Mg合金进行显微组织观察和电化学分析,探究Mn元素的添加对T6热处理状态下合金微观结构和耐蚀性的影响。结果表明,Mn添加量的提高对合金显微硬度几乎没有影响,但在合金基体中可以观察到弥散相。随着Mn含量升高,合金的耐蚀性呈现先升高后降低的趋势。添加0.360%Mn(质量分数)合金具有最佳耐蚀性,腐蚀电流密度比基础合金减少了54%。腐蚀形貌观察结果表明,Mn的添加可以显著减弱合金的点蚀趋势。Al-Si-Cu-Mg series alloys have excellent strength and toughness,but the presence of Cu-containing hardening nanoprecipitates greatly affects their corrosion resistance.For this purpose,microstructure observation and electrochemical analysis of Al-7Si-2Cu-0.6Mg alloys with different Mn alloying additions were carried out to investigate the effect of Mn addition on the microstructure and corrosion resistance of the alloys under T6 heat treatment.The results indicate that the increase in Mn addition has almost no effect on the microhardness of the alloy,but a dispersed phase can be observed in the matrix of the alloys.The corrosion resistance of the alloy tends to increase and then decrease with increasing Mn content.Compared with the base alloy,the alloy with 0.360 wt.%Mn has the best corrosion resistance,and the corrosion current density is reduced by 54%.The observation of the corrosion morphology indicates that the addition of Mn can significantly weaken the pitting corrosion trend of the alloy.The present work provides a new approach for improving the corrosion resistance of Al-Si-Cu-Mg alloys and extends the application range of these alloys.

关 键 词：AL-SI-CU-MG合金 MN含量 耐蚀性 电化学分析 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG113.231[金属学及工艺—金属材料]