微束等离子体重熔Mg-12Dy-1.1Ni合金的显微组织和腐蚀性能  

Microstructure and corrosion properties of micro-beam plasma remelted Mg-12Dy-1.1Ni alloy

作　　者：姜静 陈思琦 顾家睿 毕广利 黄健康 李元东 陈体军 马颖 JIANG Jing;CHEN Si-qi;GU Jia-rui;BI Guang-li;HUANG Jian-kang;LI Yuan-dong;CHEN Ti-jun;MA Ying(State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals(Lanzhou University of Technology),Lanzhou 730050,China;School of Material Science and Engineering,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals(Lanzhou University of Technology),Lanzhou 730050,China [2]School of Material Science and Engineering,Lanzhou University of Technology,Lanzhou 730050,China

出　　处：《Journal of Central South University》2023年第1期20-34,共15页中南大学学报（英文版）

基　　金：Projects(52001152, 51961021) supported by the National Natural Science Foundation of China;Projects(DC2020353, DC2020342, DC2022017, DC2022025, DC2022027) supported by the Undergraduate Innovation and Entrepreneurship Training Programs,China。

摘　　要：本文研究了微束等离子体重熔(MPRMed)Mg-12Dy-1.1Ni (wt%)合金的显微组织和腐蚀性能。铸态合金主要由α-Mg相、具有18R-LPSO结构的片层状Mg12DyNi相和Mg24Dy5相组成。经微束等离子体重熔后,铸态合金的晶粒尺寸显著细化至11μm,18R-LPSO相体积分数由18.3%增加至26.0%,并呈连续网状分布。电化学和浸泡实验结果表明,在0.1 mol/L NaCl溶液中,MPRMed合金的失重速率(0.31 g/(cm2·d))和腐蚀电流密度(605.3μA/cm2)均低于铸态合金,其中腐蚀电流密度较铸态合金减少了38.5%。该MPRMed合金优异的耐腐蚀性能主要源自于其均匀的显微组织、致密的腐蚀产物和连续分布的18R-LPSO相。Microstructure and corrosion properties of micro-beam plasma remelted(MPRMed) Mg-12Dy-1.1Ni(wt%)alloy were investigated. The as-cast alloy was mainly composed of α-Mg, lamellar Mg12DyNi phase with a 18R-long period stacking order(LPSO) structure, and Mg24Dy5 phase. After micro-beam plasma remelting(MPR), the grain size of the as-cast alloy was remarkably refined to 11 μm, and the amounts of 18R-LPSO phase increased from 18.3% to 26.0%and distributed as continuous network. The electrochemical and immersion tests indicated that the MPRMed alloy exhibited a lower mass loss rate 0.31 g/(cm~2·d) and corrosion current density(605.3 μA/cm~2, and ~38.5% reduction after MPR) than the as-cast alloy in 0.1 mol/L NaCl solution. The improved corrosion resistance of the MPRMed alloy was primarily ascribed to the uniform microstructure, denser corrosion products and continuous distribution of 18R-LPSO phase.

关 键 词：Mg-Dy-Ni合金 微束等离子重熔 显微组织 LPSO相 腐蚀性能 

分 类 号：TG146[一般工业技术—材料科学与工程]