Corrosion behavior of bulk two-phase Ag-25Cu alloys with different microstructures in NaCl aqueous solution  

不同显微组织的块体双相Ag-25Cu合金在NaCl溶液中的腐蚀行为（英文）

作　　者：Zhong-qiu CAO Xiao-tong YIN Zhong-qiu JIA Qiu-yue TIAN Jie LU Ke ZHANG Yan WANG 曹中秋;尹晓桐;贾中秋;田秋月;鲁捷;张轲;王艳(沈阳师范大学化学化工学院,沈阳110034;沈阳师范大学实验教学中心,沈阳110034)

机构地区：[1]College of Chemistry and Chemical Engineering,Shenyang Normal University,Shenyang 110034,China [2]Experimental Teaching Centre,Shenyang Normal University,Shenyang 110034,China

出　　处：《Transactions of Nonferrous Metals Society of China》2019年第7期1495-1502,共8页中国有色金属学报（英文版）

基　　金：Projects(51271127,51501118)supported by the National Natural Science Foundation of China;Project(2018304025)supported by Liaoning Provincial Key Research and Development Program,China;Project(201602679)supported by the Natural Science Foundation of Liaoning Province,China

摘　　要：In order to have a better understanding on the corrosion mechanisms of bulk two-phase Ag-25Cu (at.%) alloys with different microstructures, two bulk nanocrystalline Ag-25Cu alloys and one coarse grained counterpart were prepared by liquid phase reduction (LPR), mechanical alloying (MA) and powder metallurgy (PM) methods, respectively. Their corrosion behavior was investigated comparatively using electrochemical methods in NaCl aqueous solution. Results show that the microstructure of the coarse grained PMAg-25Cu alloy is extremely inhomogeneous. On the contrary, compared with PMAg-25Cu alloy, the microstructures of the nanocrystalline LPRAg-25Cu and MAAg-25Cu alloys are more homogeneous, especially for LPRAg-25Cu alloy. The corrosion rate of MAAg-25Cu alloy is higher than that of PMAg-25Cu alloy, but lower than that of LPRAg-25Cu alloy. Furthermore, the passive films formed by three Ag-25Cu alloys exhibit n-type semiconducting properties. The passive current density of LPRAg-25Cu alloy is lower than that of PMAg-25Cu alloy, but higher that of MAAg-25Cu alloy.为了更好地了解块体双相Ag-25Cu(at.%)合金的腐蚀机制,采用液相还原(LPR)、机械合金化(MA)和粉末冶金(PM)法分别制备显微组织不同的2 种纳米晶和1 种常规尺寸的Ag-25Cu 块体合金,并采用电化学方法对比研究此3 种不同显微组织Ag-25Cu 合金在NaCl 溶液中的腐蚀行为。结果表明:粉末冶金法制备的常规尺寸PMAg-25Cu 合金的显微组织极不均匀;相反,液相还原法和机械合金化法制备的纳米晶LPRAg-25Cu 和MAAg-25Cu 合金的显微组织较均匀,而纳米晶LPRAg-25Cu 合金的显微组织最均匀。MAAg-25Cu 合金的腐蚀速率高于PMAg-25Cu 合金的腐蚀速率,但低于LPRAg-25Cu 合金的腐蚀速率。3 种Ag-25Cu 合金表面形成的钝化膜均具有n 型半导体特征。LPRAg-25Cu 合金的钝化电流密度低于PMAg-25Cu 合金的钝化电流密度,但高于MAAg-25Cu 合金的钝化电流密度。

关 键 词：NANOCRYSTALLINE Ag-Cu bulk alloy mechanical alloying liquid phase reduction microstructure electrochemical corrosion 

分 类 号：TG146.32[一般工业技术—材料科学与工程]