期刊
MATERIALS & DESIGN
卷 191, 期 -, 页码 -出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.matdes.2020.108592
关键词
CALPHAD; Density function theory; Precipitates; Morphology; Fe-Ni based alloys
资金
- National Energy Research Scientific Computing Center (NERSC), a United States Department of Energy Office of Science User Facility [DE-AC02-05CH11231]
Achieving a high-volume fraction of thermodynamically stable L1(2)-type precipitates that are resistant to coarsening is of great importance for the development of low-cost Fe-Ni based austenitic steels. With the aid of computational thermodynamics, this work designed two model alloys: Fe-37.4Ni-6.1Al-2.9Ti (FNAT) and Fe-45.2Ni-5.9Al-8.5Si (FNAS). Both alloys were designed to contain a similar amount of L1(2) precipitate in Fe-Ni matrix with-out forming other precipitates. Density-Function-Theory (DFT) calculation was coupled with computational thermodynamics to predict the critical radius at which the precipitates change shape from spherical to cuboidal. The calculation results suggest that critical radius for the FNAT alloy is about two orders of magnitude larger than that for the Fe-Ni-Al-Si alloy. Phase stability and morphology of the L1(2) precipitates in these two alloys were experimentally investigated through X-ray diffraction, atom probe tomography, and scanning and transmission electron microscopy. The L1(2) precipitates in the Fe-Ni-Al-Si system were found to be cuboidal and rod shaped, with much larger size than the spherical ones in the Fe-Ni-Al-Ti system, agreeing with the calculation results.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据