Corrosion and passive behaviour of duplex stainless steel 2205 at different cooling rates in a simulated marine-environment solution
Corrosion and passive behaviour of duplex stainless steel 2205 at different cooling rates in a simulated marine-environment solution作者机构：National Construction Steel Quality Supervision and Test Centre Central Research Institute of Building and Construction Co. Ltd. Beijing 100088 China Department of Structural Steels Central Iron and Steel Research Institute Beijing 100081 China China University of Pertroleum-Beijing Beijing 102249China
出 版 物：《Journal of Iron and Steel Research International》 (国际钢铁研究杂志)
年 卷 期：2018年第25卷第9期
页 面：943-953页
核心收录：
学科分类：083002[工学-环境工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 07[理学] 08[工学] 09[农学] 0903[农学-农业资源与环境] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0713[理学-生态学]
基 金：sponsored by the National High- Tech R&D Programme of China
主 题：Duplex stainless steel Cooling rate Pitting corrosion Passive film Electrochemistry
摘 要：The corrosion and passive behaviour of duplex stainless steel 2205 at six cooling rates （1, 5, 10, 15, 20 ℃ s^-1 and water quenched） in a simulated marine-environment solution was investigated using electrochemical measurements of potentiostatic critical pitting temperature, potentiodynamic polarisation curves, electrochemical impedance spectroscopy and Mott-Schottky curves. The microstructural evolution and pitting morphologies of the specimens were visualised using an optical microscope and scanning electron microscope. The electrochemical responses of the passive film show that passivity of the steel was enhanced as the cooling rate increased; however, the threshold cooling rate was 20 ℃ s^-1, beyond which pitting corrosion resistance remained stable. Based on the analyses of microstructural evolution and pit morphologies, the proportion of the ferrite phase increased with the cooling rate and the ratio of austenite and ferrite was close to 1：1. The pitting size decreased as the cooling rate increased, and most metastable pits on specimens were located in the ferrite phase and on the ferrite-austenite interface. Thus, pitting resistance of steel is governed by the phase that provides the lowest pitting resistance equivalent number. The optimised pitting corrosion resistance for steel 2205 was achieved when it was greater than or equal to 20℃ s^-1.
维普期刊数据库