中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 6 No. 1 March 1996 |
(Department of Materials Science and Engineering Zhejiang University,Hangzhou 310027)
Abstract:The kinetics of internal chlorination of Ni-Cr-Ce alloy in chlorine at 575℃ has been studied. Internal chlorination of Ni-Cr-Ce alloy occurred to formation of CrCl2 and CeCl3 solid preeipi-tates which is thermodynamically stable and has lower vapor pressure at the temperature along grain initial corrosion stage,the internal chlorination rate nearly followed parabolic rate law, the internal chlorination was accompanied by the consumption of the alloy by volatilization corrosion which obeyed a linear rate equation,the thickness of the internal chlorination region would be governed by a paralinear rate equation. After a sufficiently long period of corrosion, the rate of internal chlorina-tion would be equal to the rate of overall metal consumption,the depth of internal chlorination op-proaches a steady state value. Addition of Ce to Ni-Cr alloy increased the degree of internal chlorina-tion
Key words: internal chlorination vapor pressure chloride