Effect of Zn on Microstructures and Corrosion Resistance of Extruded Mg-RE-Mn Alloy

Feng Mingming; Zhang Daidong; Fang Daqing

doi:10.15980/j.tzzz.2014.12.029

Views : 0 下载量: 121 CSCD: 1

Export
Share
Collection
Album

Effect of Zn on Microstructures and Corrosion Resistance of Extruded Mg-RE-Mn Alloy
Vol. 34, Issue 12, Pages: 1332-1336(2014)
Published： 2014 ，
DOI： 10.15980/j.tzzz.2014.12.029

扫描看全文

[1]冯明明,张代东,房大庆.Zn对Mg-RE-Mn合金组织和耐腐蚀性能的影响[J].特种铸造及有色合金,2014,34(12):1332-1336.

Feng Mingming, Zhang Daidong, Fang Daqing. Effect of Zn on Microstructures and Corrosion Resistance of Extruded Mg-RE-Mn Alloy. [J]. Special Casting & Nonferrous Alloys 34(12):1332-1336(2014)
[1]冯明明,张代东,房大庆.Zn对Mg-RE-Mn合金组织和耐腐蚀性能的影响[J].特种铸造及有色合金,2014,34(12):1332-1336. DOI： 10.15980/j.tzzz.2014.12.029.

Feng Mingming, Zhang Daidong, Fang Daqing. Effect of Zn on Microstructures and Corrosion Resistance of Extruded Mg-RE-Mn Alloy. [J]. Special Casting & Nonferrous Alloys 34(12):1332-1336(2014) DOI： 10.15980/j.tzzz.2014.12.029.

摘要

采用扫描电镜、XRD、电化学测试和化学浸泡试验

研究了Zn对挤压态Mg-RE-Mn镁合金显微组织以及在3.5%的NaCl溶液中耐腐蚀性能的影响。结果表明

加入Zn后

合金中有MgZn2、Mg2Zn11相生成

并显著细化了合金的晶粒。Zn能使合金的腐蚀电位正移

改善合金的耐腐蚀性能。当w（Zn）=1.5%时

合金晶粒细小

组织成分均匀

平均腐蚀速率仅为1.180mm/a。当w（Zn）=3.0%时

合金的析出相增多

并出现粗化、偏聚的趋势

以α-Mg为阳极

第二相（MgZn2等）为阴极的电偶腐蚀加剧

平均腐蚀速率为2.419mm/a。

Abstract

Effects of Zn on microstructure of an extruded Mg-RE-Mn alloy and its corrosion behavior in3.5%NaCl solution were investigated by means of scanning electron microscope（SEM）

X-ray diffractometer（XRD）

electrochemical test and chemical immersion methods.The results show that with Zn addition

secondary phase MgZn2、Mg2Zn11are generated

and the grain size in the alloys is obviously refined.Zn can improve the anti-corrosion property of the alloy by shifting the pitting potential to a positive value to some extent.With 1.5% Zn content

the grain size is decreased remarkably

and the microstructure becomes homogeneous

meanwhile

the average corrosion rate of the alloy is only 1.180mm/a.When Zn content is 3.0%

the precipitates are increased with the trend of coarsening and segregation.So a galvanic corrosion which can be formed for theα-Mg as an anode and the second phase as a cathode accelerates the corrosion of the alloy

resulting in the average corrosion rate of the alloy of 2.419mm/a.