铝硅复合对Fe32Mn7Cr3Al2Si钢氧化改性层耐蚀性的影响  

Corrosion Performance of Transition Layer at Interface of Oxide Scale/substrate Formed on Austenitic Steel Fe32Mn7Cr3Al2Si During High Temperature Oxidation

作　　者：梁泰贺 朱雪梅[1] 张振卫 王新建[1] 张彦生[1] LIANG Taihe;ZHU Xuemei;ZHANG Zhenwei;WANG Xinjian;ZHANG Yansheng(School of Materials Science and Engineering,Dalian Jiaotong University,Dalian 116028,China)

机构地区：[1]大连交通大学材料科学与工程学院,大连116028

出　　处：《中国腐蚀与防护学报》2022年第2期317-323,共7页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然科学基金(51575077)。

摘　　要：利用XRD、EPMA、阳极极化和电化学阻抗技术研究了铝硅复合合金化对Fe32Mn7Cr3Al2Si钢高温氧化诱发转变层的组织、成分及电化学腐蚀性能影响。在700和800℃空气中对Fe32Mn7Cr3Al2Si奥氏体钢进行循环氧化表面改性,形成的氧化层由内层Al_(2)O_(3)、中间层Mn_(2)SiO_(4),外层Mn_(2)O_(3)组成。经800℃空气中循环氧化160 h后,在钢基体/氧化层界面形成了厚度约20μm的贫Mn(11%)、富Cr(14%)铁素体α相转变层。相比原始Fe32Mn7Cr3Al2Si钢,贫Mn富Cr的氧化改性层在1 mol/L Na_(2)SO_(4)溶液中的自腐蚀电位由-463 mV增至248 mV,维钝电流密度由2.8μA/cm^(2)降至0.4μA/cm^(2),电荷转移电阻Rt由15.5 kΩ·cm^(2)增至69.7 kΩ·cm^(2),铝硅复合加入可增加Fe32Mn7Cr3Al2Si钢氧化诱发贫Mn层中的Cr富集,显著提高钢的耐蚀性能。The microstructure,composition and electrochemical corrosion properties of the oxidation-induced transition layer on austenitic steel Fe32Mn7Cr3Al2Si was investigated by means of XRD,EPMA,anode polarization and electrochemical impedance measurement,respectively.The Fe32Mn7Cr3Al2Si austenitic steel was intentionally oxidized at 700 and 800℃in air,respectively,the formed oxide scale was typically composed of Mn_(2)O_(3) outer sublayer,Mn_(2)SiO_(4) middle sublayer,and Al_(2)O_(3) inner sublayer.A transition layer of α-ferrite with Mn-depletion of 11%and Cr-enrichment of 14%at the interface of oxide scale/steel matrix was occurred at 800℃in air for 160 h.Compared with the original Fe32Mn7Cr3Al2Si austenitic steel,the transition layer exhibited an increased passivation ability in 1 mol/L Na_(2)SO_(4) solution,correspondingly,the free-corrosion potential increased from-463 mV(SCE)to 248 mV(SCE),the free corrosion current density decreased from the 2.8μA/cm^(2) to 0.4μA/cm^(2),and the resistant Rt increased from 15.5 kΩ·cm^(2) to 69.7 kΩ·cm^(2).It follows that Al-and Si-alloying can promote the Cr enrichment in the Mn depletion layer and therefore,improve the corrosion resistance of Fe32Mn7Cr3Al2Si austenitic steel.

关 键 词：Fe32Mn7Cr3Al2Si钢 氧化表面改性 氧化诱发转变层 阳极极化曲线 电化学阻抗 

分 类 号：TG174[金属学及工艺—金属表面处理]