珠光体组织对重轨钢U71Mn腐蚀行为的影响  

Effect of Pearlite Structure on Corrosion Behavior of U71Mn Heavy Rail Steel

作　　者：吴世杰 刘丽霞[1,2] 彭军 王晓丽[2] 焦海东 霍启男 WU Shijie;LIU Lixia;PENG Jun;WANG Xiaoli;JIAO Haidong;HUO Qinan(School of Materials and Metallurgy,Inner Mongolia University of Science and Technology,Baotou 014010,China;Inner Mongolia Key Laboratory ofAdvanced Ceramics and Devices,Baotou 014010,China;Shougang Jingtang Iron and Steel United Co.,Ltd.,Tangshan 063000,China)

机构地区：[1]内蒙古科技大学材料与冶金学院,包头014010 [2]内蒙古先进陶瓷与器件重点实验室,包头014010 [3]首钢京唐钢铁联合有限责任公司,唐山063000

出　　处：《材料导报》2021年第12期12147-12155,共9页Materials Reports

基　　金：国家自然科学基金(51664046,51874186)。

摘　　要：通过实验室加速腐蚀试验研究了不同珠光体片层间距重轨钢在模拟大气环境中的腐蚀行为,采用场发射电镜、XRD、电化学测试等方法对重轨钢组织和腐蚀结果进行了表征。不同冷却制度下所得实验用U71Mn重轨钢珠光体片层间距为155 nm、241 nm、340 nm、446 nm。随腐蚀时间延长和珠光体片层间距减小,腐蚀失重和腐蚀速率明显下降,珠光体片层间距为155 nm时,腐蚀速率最小,为0.0014 mg·cm^(-2)·h^(-1)。四种试样锈层中均含有α-FeOOH、γ-FeOOH、Fe_(3)O_(4),当珠光体片层间距减小到241 nm以下,α-FeOOH峰值明显增强,腐蚀产物中最先出现少量α-Fe_(2)O_(3),锈层形貌较为致密。珠光体组织片层间距从446 nm减小到155 nm,形成致密的保护性锈层的时间从240 h提前120 h,内锈层厚度和致密性明显提高,腐蚀480 h后珠光体片层间距最小的实验钢腐蚀电流最小,腐蚀电位最大,抗大气腐蚀性能最好。The corrosion behaviors of U71Mn heavy rail steel with different perlite lamellar spacing were studied by accelerated corrorsion test in simulated atmopheric environment.The microstructure and corrosion results of heavy rail steel were measured by FESEM,XRD and electrochemical measurement.The pearlite interlaminar spacing of U71Mn heavy rail steel under different cooling way were 155 nm,241 nm,340 nm and 446 nm.The corrosion weight loss and corrosion rate decreased significantly with the decrease of pearlite interlaminar spacing.When the pearlite lamellar spacing was 155 nm,the corrosion rate was the lowest,which was 0.0014 mg·cm^(-2)·h^(-1).There wereα-FeOOH,γ-FeOOH and Fe_(3)O_(4) in the rust layer of 4 samples.When the pearlite lamellar spacing was less than 241 nm,the peak value ofα-FeOOH was obviously enhanced,and a small amount ofα-Fe_(2)O_(3) appeared in the corrosion products,and the rust layer was relatively dense.The formation time of dense rust layer was 120 h earlier than 240 h,and the thickness and compactness of the inner rust layer were obviously improved when the pear-lite lamellar spacing decreased from 446 nm to 155 nm.The corrosion current density was minimun and corrosion potential was maximum when the pearlite interlaminar spacing was 155 nm after 480 hours of corrosion,which had the best resistance to atmospheric corrosion.

关 键 词：U71Mn重轨钢 珠光体组织 腐蚀行为 NaHSO_(3)介质 大气腐蚀 

分 类 号：TG174[金属学及工艺—金属表面处理]