Passivity degradation mechanism of UNS N08800 in simulated crevice chemistries containing reduced sulfur
Sulfur induced passivity degradation in nuclear power plant is assumed to occur at low temperature.We systemically investigate the passivity degradation of UNS N08800 in chloride and thiosulfate solutions at 20,40 and 90℃ by using polarization curves,electrochemical impedance spectroscopy(EIS),and X-ray photoelectron spectroscopy(XPS).Experimental results reveal that thiosulfate can be reduced to S0,S2 2-and S2-,adsorb on metal surface and further incorporate into the passive film.This chemical and electrochemical processes significantly depend on temperature.The evolution of pitting potentials can be ascribed to the competitive adsorption of chloride and thiosulfate on the passive surface.The passive film formed in thiosulfate solutions shows a bilayer structure,and sulfur ions can only incorporate into the outer layer.
A.Alloy B.Polarization SIMS C.Passive films
Da-Hai Xia Shizhe Song Jianqiu Wang Jing-Li Luo
Tianjin Key Laboratory of Composite and Functional Materials,School of Materials Science and Enginee Tianjin Key Laboratory of Composite and Functional Materials,School of Materials Science and Enginee CAS Key Laboratory of Nuclear Materials and Safety Assessment,Institute of Metal Research,Chinese Ac
国际会议
沈阳
英文
197-217
2017-09-26（万方平台首次上网日期，不代表论文的发表时间）