J. Mater. Sci. Technol. ›› 2018, Vol. 34 ›› Issue (8): 1419-1427.DOI: 10.1016/j.jmst.2017.11.028

Special Issue: Corrosion in 2018

• Orginal Article • Previous Articles     Next Articles

Effect of temperature on corrosion behavior of alloy 690 in high temperature hydrogenated water

Jiazhen Wangab, Jianqiu Wanga(), Hongliang Minga, Zhiming Zhanga, En-Hou Hana   

  1. a Key Laboratory of Nuclear Materials and Safety Assessment, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
    b Reactor Engineering Research Sub-Institute, Nuclear Power Institute of China, Chengdu 610213, China
  • Received:2017-07-26 Revised:2017-11-07 Accepted:2017-11-09 Online:2018-08-17 Published:2018-08-22

Abstract:

The influence of temperature on the corrosion behavior of Alloy 690 is evaluated using potentiodynamic polarization curves, electrochemical impedance spectra (EIS), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The corrosion rate of Alloy 690 reaches a local maximum at 250 °C. The kinetic control step of the growth of oxide film changes from the diffusion process of aqueous-phase ions to the growth of Cr-rich barrier layer in the temperature range of 200-300 °C. A modified double-layer model is proposed to describe the effect of temperature on the structure and composition of the oxide film.

Key words: Alloy, Polarization, EIS, SEM, TEM, High temperature corrosion