耐候钢在煤浸出液中的腐蚀研究  

Study on the Corrosion of Weathering Steels in Coal Leaching Solution

作　　者：温东辉 宋凤明 薛慧 WEN Dong-hui;SONG Feng-ming;XUE Hui(Research Institute,Baoshan Iron and Steel Co.,Ltd.,Shanghai 201900,China;Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power,Shanghai University of Electric Power,Shanghai 200090,China)

机构地区：[1]宝山钢铁股份有限公司研究院,上海201900 [2]上海电力大学上海市电力材料防护与新材料重点实验室,上海200090

出　　处：《材料保护》2022年第S01期19-26,共8页Materials Protection

摘　　要：我国运煤敞车腐蚀严重,为了研究运煤敞车腐蚀环境和腐蚀机理,分析了8种煤的浸出液成分,配制不同浓度的浸出液模拟液,并采用电化学阻抗谱、极化曲线及失重试验研究了2种耐候钢和1种普碳钢在煤浸出液中的腐蚀行为。结果显示:煤浸出液呈弱碱性,pH值在7.42~8.09范围,其中阳离子主要为Ca^(2+)、Na^+、Mg^(2+),阴离子主要为SO_(4)^(2-)和Cl^(-)。研究分析了2种耐候钢S450EW和BC550与普碳钢Q345B在煤浸出液中的电化学腐蚀行为,发现在模拟液未达到过饱和时,3种钢的极化电阻R_(p)值均随着模拟液离子浓度的提高而减小,钢的腐蚀速率增大;3种钢在煤浸出液中的腐蚀主要受阳极极化控制。在模拟液微动情况下,3种钢的腐蚀速率显著增大,在摇速60 r/min条件下3种钢的腐蚀速率分别比静态时提高4.9倍以上。S450EW钢在煤浸出液中显示了最好的耐腐蚀性能,并归因于其表面腐蚀产物膜的保护性。Coal open wagons corrode seriously in China.In order to investigate their corrosion environment and corrosion mechanism,the components of leaching solutions of 8 kinds of coals were analyzed,and simulated leaching solutions with different concentration were prepared.Subsequently,the corrosion behaviors of two weathering steels S450 EW and BC550 and one common carbon steel Q345 B in coal leaching solutions were studied by electrochemical impedance spectroscopy(EIS),polarization curve and weight loss test.Results showed that the coal leaching solutions were weakly alkaline with a pH value of 7.42~8.09,in which the cations were mainly Ca^(2+),Na^(+)and Mg^(2+),while the anions were mainly SO_(4)^(2-)and Cl^(-).Through the study and analysis on the electrochemical corrosion behavior of three steels in the coal leaching solutions,it was found that before the simulated leaching solutions reached supersaturation,the polarization resistance R_(p) value of all the three steels decreased and the corrosion rate of the steels increased with the rising of ion concentration in the simulated solutions.In addition,the corrosion of the three steels in the coal leaching solutions was mainly controlled by anodic polarization.With the perturbation of simulated solutions,the corrosion rate of three steels increased significantly.In case of a shaking with a speed of 60 r/min,the corrosion rates of the three steels increased by more than 4.9 times compared with those in static conditions.Besides,S450 EW steel exhibited the best corrosion resistance in coal leaching solutions,which was attributed to the protection provided by the corrosion product film on its surface.

关 键 词：耐候钢 煤浸出液 运煤敞车 腐蚀 

分 类 号：TG113.23[金属学及工艺—物理冶金]