高铝Fe-Mn基合金热氧化表面改性层的腐蚀行为  

Corrosion Behavior of Thermal Oxidation Layer Formed on High Aluminum Fe-Mn base Alloy

作　　者：刘昊一 朱雪梅[1] 王新建[1] 张彦生[1] LIU Haoyi;ZHU Xuemei;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,辽宁大连116028

出　　处：《大连交通大学学报》2021年第6期87-90,共4页Journal of Dalian Jiaotong University

摘　　要：在800℃空气中对Fe30Mn9Al合金进行循环氧化160 h,利用X射线衍射(XRD)和电子探针显微分析(EPMA)技术,及稳态阳极极化和暂态交流阻抗测量技术,研究了高铝Fe-Mn基合金热氧化诱发贫Mn层的形成规律及其对耐蚀性能的影响.研究结果表明:Fe30Mn9Al合金热氧化表层主要由Mn;O;、Al;O;和MnAl;O;组成,无铁氧化物存在;在氧化层与基体之间获得了厚度约为9μm、Mn含量15%的贫Mn铁素体层.相比Fe30Mn9Al合金,热氧化诱发贫Mn层在1 mol/L Na;SO;溶液中的自腐蚀电位E;从-568 mV提高至39 mV,维钝电流密度i;从21μA/cm;左右下降至1.6μA/cm,极化电阻R由3.8 kΩ·cm;增至24.8 kΩ·cm,耐蚀性能提高.The constituent and microstructure of the oxide scales formed on Fe30 Mn9 Al alloy oxidized at 800℃ in air for 160 h were investigated by X-ray diffraction and electron probe micro-analysis, and the electrochemical corrosion behavior of the oxidation-induced Mn depletion layer was evaluated by steady state anodic polarization and transient state electrochemical impedance spectroscopy. The thermal oxidation-induced Mn depletion layer about 9 μm thick between the oxide layer and the matrix is obtained and transformed to ferrite with depletion in Mn(15 at.%) and enriched in Fe(76 at.%). Compared with Fe30 Mn9 Al alloy, the Ecorr of the Mn depletion layer in 1 mol/L Na;SO;solution is increased from-568 mV to 39 mV, the i;is decreased from 21 μA/cm;to 1.6 μA/cm;, and the resistant R is increased from 3.8 kΩ·cm;to 24.8 kΩ·cm;. Thus, the corrosion resistance of the Fe30 Mn9 Al alloy is improved by the oxidation-induced Mn depletion layer.

关 键 词：Fe30Mn9Al合金 热氧化改性层 阳极极化曲线 电化学交流阻抗 

分 类 号：TG174.4[金属学及工艺—金属表面处理]