含Cr调质态桥梁用钢的腐蚀行为研究  

Study on Corrosion Behavior of Quenched and Tempered Bridge Steel with Cr

作　　者：金辉[1,2] 谌芳元 董峰辉[3] JIN Hui;CHEN Fangyuan;DONG Fenghui(Chang＇an University, Xi＇an 710064, China;Taizhou University, Taizhou 318000, China;Tongji University, Shanghai 200092, China)

机构地区：[1]长安大学,陕西西安710064 [2]台州学院,浙江台州318000 [3]同济大学,上海200092

出　　处：《热加工工艺》2018年第6期88-92,共5页Hot Working Technology

基　　金：浙江省自然科学基金项目(LY15E080003);浙江省交通厅科技项目(2013H29-1)

摘　　要：研究了不同Cr含量调质态桥梁用钢的显微组织、电化学性能和液-气界面半浸泡腐蚀性能。结果表明,不同Cr含量桥梁用钢的基体组织都为回火索氏体,但是1.1Cr和2.0Cr桥梁用钢中铁素体仍然保持着淬火马氏体的板条状形态,且碳化物相对更加细小和弥散;随着Cr含量的提高,桥梁用钢的腐蚀电位发生了正向移动,而腐蚀电流密度逐渐减小,极化电阻不断增大,桥梁用钢的耐腐蚀性从高至低为：2.0Cr桥梁用钢〉1.1Cr桥梁用钢〉0.5Cr桥梁用钢;随着Cr含量的提高,桥梁用钢的表面腐蚀程度逐渐减轻,年腐蚀速率呈逐渐降低的趋势;液-气界面上区域的腐蚀产物层厚度大于液-气界面下区域,且液-气界面上区域的Cr元素富集在外锈层区,而液-气界面下区域的Cr元素富集在内锈层区。The microstructure, electrochemical properties and liquid-gas interface semi immersion corrosion properties of the bridge steels with different Cr contents in quenched and tempered state were studied. The results show that the matrix structure of bridge steel with different cr contents is tempering sorbite, but the ferrite in 1.1Cr and 2.0Cr bridge steels still maintain the stripe shape of quenched martensite, and the carbide is relatively finer and dispersed. With the increase of Cr content, the corrosion potential of the bridge steel has a positive movement, while the corrosion current density gradually decreases, and the polarization resistance increases gradually. The corrosion resistance of the bridge steel from high to low is 2.0Cr bridge steel 〉I. 1Cr bridge steel 〉0.5Cr bridge steel. With the increase of Cr content, the corrosion degree of the bridge steel surface gradually reduces and the annual corrosion corrosion rate decreases gradually. The thickness of the corrosion product layer above the liquid air interface is larger than that under the liquid gas interface, and the Cr element in the region at the liquid air interface is enriched in the outer rust layer, while the Cr element in the region below the liquid air interface are enriched in the inner rust zone.

关 键 词：CR 桥梁用钢 极化曲线 电化学阻抗谱 半浸泡腐蚀 

分 类 号：TG174.22[金属学及工艺—金属表面处理]