Influence of heat treatment on microstructure and electrochemical behaviors of Mg-Zn binary alloys prepared by gas-phase alloying technique  

热处理对气相合金化Mg-Zn二元合金组织和电化学行为的影响

作　　者：MA Jun NIU Li-bin YAN Yu-ting GAO Chong WANG Xiao-gang 马俊;牛立斌;闫俞廷;高冲;王晓刚(College of Materials Science and Engineering,Xi’an University of Science and Technology,Xi’an 710054,China;Shaanxi Key Laboratory of Nano-materials and Technology,Xi’an University of Architecture and Technology,Xi’an 710054,China;Shaanxi Research Center of Energy Conservation and Polygeneration Engineering Technology for Silicon and Magnesium Industry,Xi’an 710055,China)

机构地区：[1]College of Materials Science and Engineering,Xi’an University of Science and Technology,Xi’an 710054,China [2]Shaanxi Key Laboratory of Nano-materials and Technology,Xi’an University of Architecture and Technology,Xi’an 710054,China [3]Shaanxi Research Center of Energy Conservation and Polygeneration Engineering Technology for Silicon and Magnesium Industry,Xi’an 710055,China

出　　处：《Journal of Central South University》2020年第3期762-771,共10页中南大学学报（英文版）

基　　金：Project(2015DFR50990-01)supported by the International Cooperation Project of Ministry of Science and Technology of China;Project(2016KF-01)supported by the Shaanxi Key Laboratory of Nano-materials and Technology,China;Project(2015CXY-01)supported by the Cooperation Project on the Integration of Industry,Education and Research of Yulin Science and Technology Bureau,China。

摘　　要：Mg-Zn binary alloys fabricated by the gas-phase alloying technique under vacuum condition were investigated in the state of initial state and after heat treatment for the microstructure and electrochemical behaviors.Different from the traditional Mg-Zn alloys preparation methods,alloys prepared by gas-phase alloying have a large number of intermetallic compounds,such as MgZn,Mg7Zn3 and MgZn2.After solution treatment,the boundary of the eutectic disappeared and the size ofα-Mg increased from 100μm to 150μm.At the same time,the value of the resistance of charge transfer increased,which indicates that the resistance of the charge transfer and the corrosion resistance of the alloys increased.After artificial aging treatment,the distribution ofα-Mg was more uniform and its size was reduced to about 50μm,and there was new eutectic structure formed.The newly formed eutectic structure forms galvanic cells with the alloy matrix,which makes the corrosion resistance of the alloy weaken.采用气相合金化技术,在真空条件下制备了Mg-Zn二元合金,研究了合金在初始状态和热处理后的组织和电化学行为。与传统的Mg-Zn合金制备方法不同,气相合金化制备的合金中含有大量的MgZn、Mg7Zn3和MgZn2金属间化合物,α-Mg的含量较低。固溶处理后,共晶界面消失,α-Mg相尺寸由100μm增加到150μm,同时在Ringer’s试液中的电化学测试结果显示电荷转移的电阻值增加,表明合金的电荷转移电阻和耐蚀性增加。经人工时效处理后,α-Mg的分布更加均匀,α-Mg相的尺寸减小到50μm左右,并且形成了新的依附于其生长的共晶组织。由于新形成的共晶组织与合金基体形成腐蚀原电池,使合金的耐蚀性减弱。

关 键 词：gas-phase alloying Mg-Zn alloy heat treatment Ringer’s solution electrochemical behavior 

分 类 号：TG156[金属学及工艺—热处理] TG146.22[金属学及工艺—金属学]