Precipitate formations with self-adaptive elemental diffusion and segregation in T92 steel
Precipitate formations with self-adaptive elemental diffusion and segregation in T92 steel
复制标题
DOI：
10.1016/j.jallcom.2016.09.190
复制
发表时间：
2017-02
影响因子：
6.2
通讯作者：
Shuangbao Wang;Jie Liu;Q. Qi;X. Chang;Si Gao;Wei Zhang;Peng Wang
中科院分区：
文献类型：
--
作者：
Shuangbao Wang;Jie Liu;Q. Qi;X. Chang;Si Gao;Wei Zhang;Peng Wang
A detailed characterization of the composition and evolution of precipitates during thermal exposure (0–10000 h at 650 °C) of T92 steel was carried out using a combination of transmission electron microscopy (TEM), high angle annular dark field (HAADF) imaging, energy-dispersive X-ray spectrometry (EDS) analysis, scanning electron microscopy (SEM) and first-principles calculations. It is shown that MX in T92 steel can be expressed as V/Nb(C,N) rather than complete solid-solution (V,Nb)(C,N) in terms of composition. The segregation of P and S elements in the MX precipitates was found after normalization. Meanwhile the slow segregation of Si from the matrix into the MX took place during a long-term thermal exposure. The nucleation and growth of M23C6carbides adjacent to the MX micrograin boundary carbonitrides always accompany by the diffusion of C and S from the neighboring MX, and the segregation of W and Mo from the matrix, respectively. Similarly this elemental diffusion behavior of W and Mo, as well as the segregation of Si, P and S were also found for the nucleation and growth of Laves phase in contact with M23C6. Our results indicate that these precipitates formation in T92 steel is a special process with self-adaptive elemental diffusion and segregation.
