海洋环境用热轧304L不锈钢-A36碳钢复合钢板的腐蚀行为研究  

Corrosion Behaviour of Hot-rolled 304L Stainless Steel-A36 Carbon Steel Composite Steel Plate for Marine Environment

作　　者：刘叶诚 郑志斌 龙骏 徐志彪 郑开宏 焦四海[4] 殷福星 LIU Yecheng;ZHENG Zhibin;LONG Jun;XU Zhibiao;ZHENG Kaihong;JIAO Sihai;YIN Fuxing(School of Rail Traffic,Wuyi University,Guangdong Jiangmen 529000,China;Guangdong Provincial Key Laboratory of Metal Toughening Technology and Application,National Engineering Research Center of Powder Metallurgy of Titanium&Rare Metals,Institute of New Materials,Guangdong Academy of Sciences,Guangzhou 510650,China;Guangdong Provincial Iron Matrix Composite Engineering Research Center,Guangzhou 510650,China;Baoshan Iron&Steel Co.,Ltd.,Shanghai 201900,China)

机构地区：[1]五邑大学轨道交通学院,广东江门529000 [2]广东省科学院新材料研究所国家钛及稀有金属粉末冶金工程技术研究中心广东省金属强韧化技术与应用重点实验室,广州510650 [3]广东省钢铁基复合材料工程研究中心,广州510650 [4]宝山钢铁股份有限公司,上海201900

出　　处：《表面技术》2024年第14期75-86,共12页Surface Technology

基　　金：国家重点研发计划(2021YFB3701704):广东省科学院专项资金项目(2022GDASZH-2022010103,2021GDASYL-20210102002);第八届中国科协青年人才托举工程(2022QNRC001);广州市青年科技人才托举项目(QT20220101075)。

摘　　要：目的探究304L不锈钢和A36碳钢热轧复合钢板中不锈钢覆层、碳钢基体以及不锈钢-碳钢复合界面在海洋大气环境及海水浸没环境中的腐蚀行为与腐蚀机理。方法采用中性盐雾实验和电化学实验模拟了海洋大气环境及海水浸没环境,对304L不锈钢-A36碳钢热轧复合钢板的腐蚀机理进行了全面评估。利用扫描电子显微镜(SEM)和能量色散光谱(EDS)表征复合材料界面的微观结构和局部元素分布,使用X射线衍射仪(XRD)表征了腐蚀产物的成分和化合价。结果在复合界面上存在一个明显的元素过渡区域。2种钢复合界面结合平滑,结合质量良好,轧制对2种钢复合界面处的组织无明显影响。当中性盐雾实验进行到96 h时,复合界面的腐蚀速率开始超越碳钢基体的腐蚀速率。实验结束时,复合界面与碳钢基体的腐蚀失重量分别达到582g/m^(2)和468g/m^(2),复合界面在海洋大气环境中的腐蚀速率为碳钢基体的1.24倍。此外,在复合界面碳钢侧的腐蚀产物中观察到富氯层。在电化学实验中,复合界面显示出了比碳钢基体更小的阻抗,这使复合界面在海水浸没环境中的腐蚀速率为碳钢基体的1.13倍。在复合界面处发现电偶腐蚀效应,加速了A36碳钢侧的腐蚀。开路电位的测试结果表明,复合界面的开路电位与耐蚀性较差的碳钢的开路电位接近,不同不锈钢-碳钢面积比复合界面的开路电位变化较小。结论在不同海洋腐蚀环境中,复合界面的腐蚀速率均大于覆层及基体的腐蚀速率,在海洋大气环境中尤为严重,复合界面碳钢部分的小面积暴露将导致材料的耐腐蚀性严重下降,在实际工程使用中应避免复合界面,尤其是复合界面碳钢部分的直接暴露。Corrosion is one of the main causes of material failure.Steel components used for marine construction,such as steel supports for coastal airports,steel structures for sea-spanning bridges,offshore platforms and steel plates for island buildings,etc.,cause a large amount of economic losses due to corrosion every year.The work aims to investigate the corrosion behavior and corrosion mechanism of cladding,carbon steel substrate and stainless steel-carbon steel composite interface in 304L stainless steel and A36 carbon steel hot-rolled composite steel plate in marine atmospheric environment and seawater immersion environment.Neutral salt spray test and electrochemical test were used to simulate the different marine environments.Scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS)were used to characterize the microstructure and local elemental distribution at the composite interface,and X-ray diffractometry(XRD)was used to characterize the composition and valence of the corrosion products.A clear elemental transition region existed at the composite interface.The combination of the two steel composite interfaces was smooth and the bonding quality was good,and rolling had no significant effect on the microstructure at the composite interfaces of the two steels.When the neutral salt spray test was carried out for 96 h,the corrosion rate of the composite interface began to exceed that of the carbon steel substrate.At the end of the test,the corrosion mass loss of the composite interface and carbon steel substrate reached 582 g/m^(2) and 468 g/m^(2),respectively,and the corrosion rate of the composite interface in the marine atmosphere was 1.24 times of that of the carbon steel substrate.In addition,a chlorine-rich layer was observed in the corrosion products on the carbon steel side of the composite interface.In electrochemical tests,the composite interface showed smaller impedance than the carbon steel substrate,which resulted in a corrosion rate of 1.13 times that of the carbon steel substrate for th

关 键 词：金属复合材料 不锈钢 碳钢 腐蚀 海洋环境 

分 类 号：TG172[金属学及工艺—金属表面处理]