| 论文简介 |
The Ni-based alloys Incoloy 800, Incoloy 825, Inconel 625, and Hastelloy C-276 exposed to subcritical water (350° C, 25 MPa) and supercritical water (450° C, 25 MPa) with high concentrations of chloride and oxygen were analyzed by usingscanning electron microscopy, X-ray di ff raction, and X-ray photoelectron spectroscopy. There is a strong synergistic effect between salt and oxygen, leading to severe corrosion. The selective dissolution of nickel is the severest of all alloying elements, and a stable oxide in oxidizing condition is formed by chromium. Molybdenum improves the resistance to pitting corrosion when chromium is present. Without molybdenum, Incoloy 800 exhibits the severest pitting corrosion of the test alloys under subcritical condition. Inconel 625 and Hastelloy C-276 exhibit good corrosion resistance under the condition of oxygen and salt existing. NiO, NiCr2O4, and Cr2O3 are the three main components of oxidefi lms on Ni-based alloys. The possible corrosion mechanisms of Ni-based alloys are discussed |
(创新港)
