Progress in Understanding Corrosion in Supercritical Water Systems
Supercritical water (SCW) has been used as a high efficiency heat transfer medium in fossil-based power plants for over three decades. In recent years SCW is being examined as a coolant for the next generation nuclear reactors, because it can provide for higher thermal efficiency and plant simplification as compared to current light water reactors. However, corrosion has been identified as a critical materials issue because of the oxidative nature of supercritical water. In this regard, materials selection for SCW nuclear reactors is far more stringent than fossil-based power plants because of smaller component thicknesses, radiation effects (e. g., swelling, embrittlement, and accelerated segregation), and the relatively less understood effects of SCW radiolysis on corrosion. A number of Cr-containing ferritic steels are being evaluated for corrosion in SCW environment at temperatures up to 600℃ for exposure durations of several weeks. These steels develop a distinct three-layered oxide structure, consisting of an outer magnetite layer, an inner Fe-Cr oxide spinel layer, and an internal oxidation layer. Surface modification has been shown to improve oxidation resistance of these steels. Austenitic steels exhibited a higher oxidation resistance, but in some cases oxide spallation was observed. Oxide spallation in these steels can be favorably affected by grain boundary engineering using thermo-mechanical treatments.
Chen, Y. Kruizenga, A. Ren, X. Tan,L. Yang, Y. Sridharan, K. Anderson, M.H. Allen,T.R.
Department of Engineering Physics University of Wisconsin Madison, WI, 53706 USA
国际会议
上海
英文
128-137
2007-03-12（万方平台首次上网日期，不代表论文的发表时间）