The roles of Ni segregation on the oxidation kinetics of austenitic steel 316L exposed to oxygen-containing liquid Pb-Bi eutectic
作者
单位
1Shaanxi Key Laboratory of Advanced Nuclear Energy and Technology、School of Nuclear Science and Technology、Xi’an Jiaotong University、Xi’an、Shaanxi 710049、P.R. China 2China Institute of Atomic Energy、P.O. Box 275-92、Beijing 102413、China
关键词
收录来源
International Corrosion Congress · 第22届国际腐蚀大会
摘要
The micro -to-atomic structure of the oxide scale formed on 316L steel exposed to oxygen-containing liquid Pb-Bi eutectic at 550° C is characterized by SEM-EDS, EBSD, FIB-TEM and synchrotron radiation micro-XRD. Nickel that was believed to be de trimental to steel corrosion in Pb -Bi is revealed to be beneficial on retarding the oxidation kinetics. Ni does not oxidize and exists as metallic Ni -rich nanophase in the internal oxidation zone (IOZ). The inward diffusion of Ni from IOZ to the steel base causes the segregation of coarse Ni -rich precipitates on grain boundaries and the steel/IOZ interface, which hinders both the intergranular and trans-granular diffusion. Schematics illustrating the roles of nonreactive Ni on the oxidation kinetics of austenitic 316L in oxygen-containing liquid LBE.