Mn对不同纯度Mg-Al合金组织与性能影响的研究  

Effect of Mn on the Microstructure and Properties of Mg-Al Alloys of Different Purity

作　　者：吴雄 刘洪旭 敬学锐 佘加[1,2] 汤爱涛 张丁非[1,2] 章建跃 WU Xiong;LIU Hongxu;JING Xuerui;SHE Jia;TANG Aitao;ZHANG Dingfei;ZHANG Jianyue(College of Materials Science and Engineering,Chongqing University,Chongqing 400044,China;National Engineering Research Center for Mg Alloys,Chongqing 400044,China;Department of Materials Science and Engineering,The Ohio State University,Columbus OH 43210,USA)

机构地区：[1]重庆大学材料科学与工程学院,重庆400044 [2]国家镁合金材料工程技术研究中心,重庆400044 [3]俄亥俄州立大学材料学院与工程系,俄亥俄州哥伦布市43210,美国

出　　处：《精密成形工程》2024年第11期1-9,共9页Journal of Netshape Forming Engineering

基　　金：国家自然科学基金(52471117)。

摘　　要：目的探讨Mn添加对高杂质含量镁制备镁合金Mg-Al-xMn性能的影响,并对比高杂质镁与工业纯镁制备的同成分Mg-6Al-1Mn合金的性能差异。方法通过熔炼和挤压方法制备4种不同成分的Mg-Al-xMn合金(AM合金),通过金相显微镜(OM)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)等对合金的微观组织进行了表征。采用万能力学试验机测试了合金的力学性能,并通过析氢实验、浸泡失重实验和电化学实验等手段评估了合金的耐腐蚀性能,同时利用SEM表征了合金腐蚀后的形貌。结果在高杂质镁制备的镁合金中,AM61合金由于形成了弥散分布的Al_(8)Mn_(5)相,表现出最细小的微观组织和最佳的力学性能,此外,Mn吸收了Fe元素并形成了Al-Fe-Mn化合物,该合金的耐腐蚀性能也显著提升,在3.5%(质量分数)NaCl溶液中浸泡24 h后腐蚀速率为3.87 mm/a,较Mg-6Al合金的(129.74 mm/a)提高约33倍。最终,高杂质镁和工业纯镁制备的AM61合金微观结构和综合性能十分接近。结论Mn元素能够改善由高杂质含量纯镁所制备的Mg-Al合金的微观结构和力学性能,并显著提高其腐蚀性能至接近甚至达到工业纯镁制备合金的水平。这表明通过合理添加Mn,可以有效提升高杂质镁的工程应用潜力。The work aims to investigate the effect of Mn on the properties of Mg-Al-xMn alloys prepared from high impu-rity Mg,and compare the property differences between Mg-6Al-1Mn alloys of the same composition prepared from high impu-rity Mg and commercial pure Mg.Four different compositions of Mg-Al-xMn alloys(AM alloys)were prepared by melting and extrusion.The microstructure of the alloys was characterized with optical microscopy(OM),X-ray diffraction(XRD),and scanning electron microscopy(SEM).The mechanical properties of the alloys were tested with a universal testing machine.The corrosion resistance of the alloys was evaluated through hydrogen evolution tests,weight loss immersion tests,and electro-chemical experiments,and the alloy morphology after corrosion was characterized by SEM.Among the Mg alloys prepared from high impurity Mg,the AM61 alloy showed the finest microstructure and the best mechanical properties due to the forma-tion of the dispersive Al_(8)Mn_(5)phase.Additionally,the corrosion resistance of the alloy was significantly improved by the forma-tion of Al-Fe-Mn compounds from the combination of Mn and Fe.The corrosion rate of AM61 alloy was 3.87 mm/a after 24 h immersion in 3.5wt.%NaCl solution,which was about 33 times lower than that of Mg-6Al alloy(129.74 mm/a).Ultimately,the microstructure and overall properties of AM61 alloys prepared from high impurity and commercial pure magnesium were very similar.Mn can refine the microstructure and enhance the mechanical properties of Mg-Al alloys prepared from high impurity Mg and significantly improve their corrosion resistance.The corrosion rate approaches or even matches that of alloys prepared from commercial pure Mg.This indicates that through appropriate Mn addition,the engineering application potential of high impurity Mg can be effectively enhanced.

关 键 词：镁合金 杂质含量 微观组织 力学性能 腐蚀 

分 类 号：TG146.22[一般工业技术—材料科学与工程]