摘要
采用真空电弧熔炼技术制备出FeCrMnAlCu_(x)(x=0,0.5,1.0,1.5,2.0)高熵合金,通过XRD、SEM、EDS对合金的相结构及腐蚀前后的微观组织进行表征,利用动电位极化曲线、EIS、XPS以及浸泡实验对合金在0.5mol/LH_(2)SO_(4)溶液中的腐蚀性能进行分析。结果表明,Cu元素的加入促进了合金中fcc相的形成,使合金由单一bcc结构转变为bcc+fcc双相混合结构。5种成分的高熵合金具有典型的枝晶形貌,随着Cu含量的增加,晶粒逐渐细化,组织逐渐均匀。FeCrMnAlCu_(1.5)高熵合金的腐蚀电位最高(-0.363V),腐蚀电流密度最小(2.148×10^(-5)A/cm^(2)),合金的耐蚀性随着Cu含量的增加先提高后下降,当x=2.0时,腐蚀电位减小到-0.394V,电流密度增大到2.865×10^(-4)A/cm^(2),其耐蚀性能仍优于未添加Cu元素的合金。腐蚀后合金截面处形成了复合氧化物保护膜,有效降低了合金在0.5mol/LH_(2)SO_(4)溶液中的腐蚀速率。
This study employed vacuum arc melting technique to fabricate FeCrMnAlCu_(x)(x=0,0.5,1.0,1.5,2.0)high-entropy alloys.The phase structure and microstructure of the alloys before and after corrosion were characterized using XRD,SEM,and EDS.The corrosion behavior of the alloys in 0.5 mol/L H_(2)SO_(4) solution was analyzed through potentiodynamic polarization curves,EIS,XPS,and immersion tests.The results indicate that the addition of Cu promotes the formation of the fcc phase in the alloy,transforming the single bcc structure into the mixed bcc+fcc dual-phase structure.The high-entropy alloys with five different composition exhibit a typical dendritic morphology.With increasing the Cu content,the grains are gradually refined,and the microstructure becomes more uniform.The FeCrMnAlCu_(1.5) high-entropy alloy has the highest corrosion potential(-0.363 V)and the lowest corrosion current density(2.148×10^(-5) A/cm^(2)).The corrosion resistance of the alloy is initially improved and then deteriorates with increasing the Cu content.At x=2.0,the corrosion potential decreases to-0.394 V,the current density increases to 2.865×10^(-4) A/cm^(2),yet its corrosion resistance is still superior to that of the alloy without Cu addition.After corrosion,a composite oxide protective film forms on the cross-section of the alloy,effectively reducing its corrosion rate in 0.5 mol/L H_(2)SO_(4) solution.
作者
冯力
王梦琪
赵燕春
李邱达
Feng Li;Wang Mengqi;Zhao Yanchun;Li Qiuda(School of Materials Science and Engineering,Lanzhou University of Technology,Lanzhou 730050,China;State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals,Lanzhou 730050,China;China National Nuclear Power Operation and Management Corporation,Haiyan 313400,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2024年第1期85-94,共10页
Rare Metal Materials and Engineering
基金
中核核电运行管理有限公司研发项目(QS4FY-22003224)。
关键词
高熵合金
微观组织
耐蚀性
氧化膜
high-entropy alloys
microstructure
corrosion resistance
oxide film
