Optimization of B2/L21 hierarchical precipitate structure to improve creep resistance of a ferritic Fe-Ni-Al-Cr-Ti superalloy via thermal treatments

SCRIPTA MATERIALIA

卷:161

Article

Song, Gian¹  Hong, Soon Jik¹  Lee, Jin Kyu¹  Song, Sung Ho¹  Hong, Sung Hwan²  Kim, Ki Buem²  Liaw, Peter K.³ 

[1] Kongju Natl Univ, Div Adv Mat Engn, Cheonan 330717, Chungnam, South Korea

[2] Sejong Univ, Fac Nanotechnol & Adv Mat Engn, Seoul 143747, South Korea

[3] Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA

关键词: Ferritic alloys;    Precipitation;    Heat-treatment;    Coherency;    Elastic strain;   

DOI  :  10.1016/j.scriptamat.2018.10.004

来源: Elsevier

【 摘 要 】

The effect of precipitate structures of a B2-NiAl/L2(1)-Ni2TiAl hierarchical precipitate-strengthened ferritic alloy on the precipitate/matrix interface, elastic strain, and creep resistance has been investigated by systematic heat treatments and creep experiments. The experimental results reveal that the highest creep strength was achieved in a heat-treated sample containing the largest coherent precipitate with fine internal networks, whereas the semi-coherent precipitate results in a sharp drop of the creep strength. It was found that the strong elastic strain field, affected by the internal structure within the precipitate, plays a crucial role in improving the creep resistance. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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