Please wait a minute...
金属学报  2018, Vol. 54 Issue (8): 1141-1149    DOI: 10.11900/0412.1961.2017.00484
  本期目录 | 过刊浏览 |
铸态和锻造态Mg-5Y-7Gd-1Nd-0.5Zr合金腐蚀行为对比研究
刘金辉1,2, 宋影伟1(), 单大勇1, 韩恩厚1
1 中国科学院金属研究所核用材料与安全评价重点实验室 沈阳 110016
2 东北大学材料科学与工程学院 沈阳 110819
Comparative Study on Corrosion Behavior of Cast and Forged Mg-5Y-7Gd-1Nd-0.5Zr Alloys
Jinhui LIU1,2, Yingwei SONG1(), Dayong SHAN1, En-Hou HAN1
1 Key Laboratory of Nuclear Materials and Safety Assessment, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
2 School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China
全文: PDF(7413 KB)   HTML
摘要: 

采用SEM、XRD和EDS等手段观察对比了铸态和锻造态稀土镁合金Mg-5Y-7Gd-1Nd-0.5Zr (EW75)的显微组织,分析了2种状态合金中的相组成及第二相的化学成分,采用腐蚀形貌观察、失重率和电化学测试对比了2个样品的耐蚀性。结果表明,铸态EW75合金中晶粒较大,大尺寸的骨骼状第二相沿晶界分布;锻造态EW75合金中晶粒较小,细小的颗粒状第二相弥散分布在晶界上。与铸态EW75合金相比,锻造态EW75合金中的微电偶腐蚀较弱,表面膜更均匀致密,耐蚀性更好。

关键词 镁合金铸态锻造态第二相表面膜微电偶腐蚀    
Abstract

Magnesium and its alloys have become increasingly attractive in the automotive, 3C products and aerospace industries because of their advantages such as low density and high specific strength. In recent years, rare earth-Mg alloys have attracted much attention due to their high mechanical properties at room and elevated temperatures. Adjusting the microstructures by deformation treatment is a common method to improve the mechanical properties of Mg alloys. The microstructure especially the size, volume fraction and distribution of second phases in rare earth-Mg alloys will be changed during deformation treatment, which has a great effect on the corrosion resistance of Mg alloys. However, the studies on the effect of deformation treatment on the corrosion resistance of rare earth-Mg alloys are far away from sufficient. In this work, the corrosion behavior of cast and forged Mg-5Y-7Gd-1Nd-0.5Zr (EW75) alloys were studied by using SEM, XRD, mass loss measurements and electrochemical tests. The results indicate that the second phases are distributed along the grain boundaries of cast and forged EW75 alloys. Meanwhile, the second phases in forged EW75 alloy are finer and lower volume fraction than that in cast EW75 alloy. The micro-galvanic corrosion of the forged EW75 alloy is weaker in comparison with the cast EW75 alloy owing to the smaller size and lower volume fraction of second phases as well more compact surface film, resulting in the better corrosion resistance.

Key wordsMg alloy    cast    forged    second phase    surface film    micro-galvanic corrosion
收稿日期: 2017-11-20     
ZTFLH:  O646  
基金资助:国家重点研发计划项目No.2016YFB0301105和国家自然科学基金项目No.51471174
作者简介:

作者简介 刘金辉,男,1991年生,博士生

引用本文:

刘金辉, 宋影伟, 单大勇, 韩恩厚. 铸态和锻造态Mg-5Y-7Gd-1Nd-0.5Zr合金腐蚀行为对比研究[J]. 金属学报, 2018, 54(8): 1141-1149.
Jinhui LIU, Yingwei SONG, Dayong SHAN, En-Hou HAN. Comparative Study on Corrosion Behavior of Cast and Forged Mg-5Y-7Gd-1Nd-0.5Zr Alloys. Acta Metall Sin, 2018, 54(8): 1141-1149.

链接本文:

https://www.ams.org.cn/CN/10.11900/0412.1961.2017.00484      或      https://www.ams.org.cn/CN/Y2018/V54/I8/1141

图1  铸态和锻造态EW75合金表面微观形貌
图2  图1中γ和β相的EDS谱
图3  铸态和锻造态EW75合金蚀刻后表面形貌
图4  铸态和锻造态EW75合金的XRD谱
图5  铸态和锻造态EW75合金在3.5%NaCl溶液中分别浸泡60 h和7 d后的表面微观形貌
图6  铸态EW75合金在3.5%NaCl溶液中浸泡不同时间并清除腐蚀产物后的微观形貌
图7  锻造态EW75合金在3.5%NaCl溶液中浸泡不同时间并清除腐蚀产物后的表面微观形貌
图8  铸态和锻造态EW75合金在3.5%NaCl溶液中的动电位极化测试结果
EW75 Ecorr / V icorr / (μAcm-2) bc / (-mVdec-1)
Cast
Forged
-1.75
-1.75
87.9
46.4
175
159
表1  EW75合金极化曲线的拟合结果
图9  铸态和锻造态EW75合金在3.5%NaCl溶液中的EIS及拟合电路
EW75 Rs
Wcm2
Qdl
mScm-2s-n
ndl Rt
Wcm2
Qf
mScm-2s-n
nf Rf
Wcm2
L
Hcm2
RL
Wcm2
Cast 19.04 19.04 0.93 220 5081 0.85 119.1 14120 2222
Forged 18.86 17.96 0.93 262 5910 0.71 222.6 14340 1764
表2  EIS拟合结果
图10  铸态和锻造态EW75合金在3.5%NaCl溶液中浸泡前后微电偶腐蚀截面示意图
图11  铸态和锻造态EW75合金在3.5%NaCl溶液中浸泡前后表面膜的形成截面示意图
[1] Pollock T M.Weight loss with magnesium alloys[J]. Science, 2010, 328: 986
[2] Westengen H, Rashed H M M A. Magnesium: Alloying [A]. Reference Module in Materials Science and Materials Engineering[C]. Amsterdam: Elsevier, 2016: 1
[3] Mordike B L, Ebert T.Magnesium: Properties-applications-potential[J]. Mater. Sci. Eng., 2001, A302: 37
[4] Song Y W, Shan D Y, Chen R S, et al.Investigation of surface oxide film on magnesium lithium alloy[J]. J. Alloys Compd., 2009, 484: 585
[5] Ding W J, Zeng X Q.Research and applications of magnesium in China[J]. Acta Metall. Sin., 2010, 11: 1450.(丁文江, 曾小勤. 中国Mg材料研发与应用[J]. 金属学报, 2010, 11: 1450)
[6] Song G, Atrens A.Recent insights into the mechanism of magnesium corrosion and research suggestions[J]. Adv. Eng. Mater., 2007, 9: 177
[7] Zhao X, Shi L L, Xu J.A comparison of corrosion behavior in saline environment: rare earth metals (Y, Nd, Gd, Dy) for alloying of biodegradable magnesium alloys[J]. J. Mater. Sci. Technol., 2013, 29: 781
[8] Chu P W, Marquis E A.Linking the microstructure of a heat-treated WE43 Mg alloy with its corrosion behavior[J]. Corros. Sci., 2015, 101: 94
[9] Kang Y H, Wu D, Chen R S, et al.Microstructures and mechanical properties of the age hardened Mg-4. 2Y-2. 5Nd-1Gd-0. 6Zr (WE43) microalloyed with Zn[J]. J. Magnes. Alloys, 2014, 2: 109
[10] Wu D, Li S Q, Hong M, et al.High cycle fatigue behavior of the forged Mg-7Gd-5Y-1Nd-0.5Zr alloy[J]. J. Magnesium Alloys, 2014, 2: 357
[11] Zhen R, Sun Y S, Bai J, et al.Microstructures and mechanical properties of Mg-(11—13)Gd-1Zn alloys[J]. Acta Metall. Sin., 2012, 48: 733(甄睿, 孙扬善, 白晶等. Mg-(11—13)Gd-1Zn变形镁合金的组织和力学性能[J]. 金属学报, 2012, 48: 733)
[12] Zheng W C, Li S S, Tang B, et al.Effect of mischmetal on solidification microstructure and mechanical properties of AZ91D magnesium alloy[J]. Acta Metall. Sin., 2006, 42: 835(郑伟超, 李双寿, 汤彬等. 混合稀土对AZ91D镁合金组织和力学性能的影响[J]. 金属学报, 2006, 42: 835)
[13] Liu J H, Song Y W, Shan D Y, et al.Different microgalvanic corrosion behavior of cast and extruded EW75 Mg alloys[J]. J. Electrochem. Soc., 2016, 163: C856
[14] Liu J H, Song Y W, Chen J C, et al.The special role of anodic second phases in the micro-galvanic corrosion of EW75 Mg alloy[J]. Electrochim. Acta, 2016, 189: 190
[15] Song Y W, Han E H, Shan D Y, et al.The role of second phases in the corrosion behavior of Mg-5Zn alloy[J]. Corros. Sci., 2012, 60: 238
[16] Song Y W, Shan D Y, Chen R S, et al.Effect of second phases on the corrosion behaviour of wrought Mg-Zn-Y-Zr alloy[J]. Corros. Sci., 2010, 52: 1830
[17] Zhang T, Shao Y W, Meng G Z, et al.Corrosion of hot extrusion AZ91 magnesium alloy: I—Relation between the microstructure and corrosion behavior[J]. Corros. Sci., 2011, 53: 1960
[18] Zhang T, Meng G Z, Shao Y W, et al.Corrosion of hot extrusion AZ91 magnesium alloy. Part II: Effect of rare earth element neodymium (Nd) on the corrosion behavior of extruded alloy[J]. Corros. Sci., 2011, 53: 2934
[19] Neil W C, Forsyth M, Howlett P C, et al.Corrosion of magnesium alloy ZE41—The role of microstructural features[J]. Corros. Sci., 2009, 51: 387
[20] Neil W C, Forsyth M, Howlett P C, et al.Corrosion of heat treated magnesium alloy ZE41[J]. Corros. Sci., 2011, 53: 3299
[21] Song G L, Atrens A, Wu X L, et al.Corrosion behaviour of AZ21, AZ501 and AZ91 in sodium chloride[J]. Corros. Sci., 1998, 40: 1769
[22] Song Y W, Han E-H, Shan D, et al The role of second phases in the corrosion behavior of Mg-5Zn alloy[J]. Corros. Sci., 2012, 60: 238
[23] Song Y W, Han E-H, Shan D Y, et al The effect of Zn concentration on the corrosion behavior of Mg-xZn alloys[J]. Corros. Sci., 2012, 65: 322
[24] Liu Q.Reseach progress on plastic deformation mechanism of Mg alloys[J]. Acta Metall. Sin., 2010, 11: 1458(刘庆. 镁合金塑性变形机理研究进展[J]. 金属学报, 2010, 11: 1458)
[25] Zhao D Q, Zhou J X, Liu Y T, et al.Microstructure and mechanical properties of Mg-4Zn-2Al-2Sn alloys extruded at low temperatures[J]. Acta Metall. Sin., 2014, 50: 41(赵东清, 周吉学, 刘运腾等. 低温挤压Mg-4Zn-2Al-2Sn合金的组织与力学性能研究[J]. 金属学报, 2014, 50: 41)
[26] Xia X S, Chen Q, Zhao Z D, et al.Microstructure, texture and mechanical properties of coarse-grained Mg-Gd-Y-Nd-Zr alloy processed by multidirectional forging[J]. J. Alloys Compd., 2015, 623: 62
[27] Li T, Zhang K, Du Z W, et al.Characterization of β precipitate phase in Mg-7Gd-5Y-1Nd-0.5Zr alloy[J]. J. Rare Earths, 2013, 31: 410
[28] Li T, Du Z W, Zhang K, et al.Morphology and crystallography of β precipitate phase in Mg-Gd-Y-Nd-Zr alloy[J]. Trans. Nonferrous Met. Soc. China, 2012, 22: 2877
[29] Wang S D, Xu D K, Wang B J, et al.Effect of solution treatment on the fatigue behavior of an as-forged Mg-Zn-Y-Zr alloy[J]. Sci. Rep., 2016, 6: 23955
[30] Zhang X, Zhang K, Li X-G, et al.Comparative study on corrosion behavior of as-cast and extruded Mg-5Y-7Gd-1Nd-0. 5Zr alloy in 5% NaCl aqueous solution[J]. Trans. Nonferrous Met. Soc. China, 2012, 22: 1018
[31] Song G L, Unocic K A.The anodic surface film and hydrogen evolution on Mg[J]. Corros. Sci., 2015, 98: 758
[1] 张阳, 邵建波, 陈韬, 刘楚明, 陈志永. Mg-5.6Gd-0.8Zn合金多向锻造过程中的变形机制及动态再结晶[J]. 金属学报, 2020, 56(5): 723-735.
[2] 邓丽萍,崔凯旋,汪炳叔,向红亮,李强. AZ31镁合金室温多道次压缩过程微观组织和织构演变的研究[J]. 金属学报, 2019, 55(8): 976-986.
[3] 周博, 隋曼龄. AZ31镁合金拉伸扭折带结构的产生及交互作用机制[J]. 金属学报, 2019, 55(12): 1512-1518.
[4] 石章智, 张敏, 黄雪飞, 刘雪峰, 张文征. 可时效强化Mg-Sn基合金的研究进展[J]. 金属学报, 2019, 55(10): 1231-1242.
[5] 曾荣昌, 崔蓝月, 柯伟. 医用镁合金:成分、组织及腐蚀[J]. 金属学报, 2018, 54(9): 1215-1235.
[6] 王光东, 田妮, 何长树, 赵刚, 左良. DC铸造Al-12Si-0.65Mg-xMn合金中第二相的形成[J]. 金属学报, 2018, 54(7): 1059-1067.
[7] 刘晏宇, 毛萍莉, 刘正, 王峰, 王志. Schmid因子的理论计算及其在镁合金高速变形过程中的应用[J]. 金属学报, 2018, 54(6): 950-958.
[8] 吴国华, 陈玉狮, 丁文江. 高性能镁合金凝固组织控制研究现状与展望[J]. 金属学报, 2018, 54(5): 637-646.
[9] 李旭东, 毛萍莉, 刘晏宇, 刘正, 王志, 王峰. 高应变速率下Mg-3Zn-1Y镁合金的各向异性及变形机制[J]. 金属学报, 2018, 54(4): 557-565.
[10] 熊守美, 杜经莲, 郭志鹏, 杨满红, 吴孟武, 毕成, 曹永友. 镁合金压铸过程界面传热行为及凝固组织结构的表征与模拟研究[J]. 金属学报, 2018, 54(2): 174-192.
[11] 陈树君, 王宣, 袁涛, 李晓旭. 镁合金焊缝液化裂纹敏感性及预测方法探究[J]. 金属学报, 2018, 54(12): 1735-1744.
[12] 谢广明, 马宗义, 薛鹏, 骆宗安, 王国栋. 工具转速对搅拌摩擦加工Mg-Zn-Y-Zr耐热镁合金超塑性行为的影响[J]. 金属学报, 2018, 54(12): 1745-1755.
[13] 马宗义, 商乔, 倪丁瑞, 肖伯律. 镁合金搅拌摩擦焊接的研究现状与展望[J]. 金属学报, 2018, 54(11): 1597-1617.
[14] 王慧远, 张行, 徐新宇, 查敏, 王珵, 马品奎, 管志平. 超塑性轻合金组织稳定性的研究进展及展望[J]. 金属学报, 2018, 54(11): 1618-1624.
[15] 郭靖,郭汉杰,方克明,段生朝,石骁,杨文晟. 钢中第二相粒子形貌预报理论和检测方法[J]. 金属学报, 2017, 53(7): 789-796.