Precipitates and Particles Coarsening of 9Cr–1.7W–0.4Mo–Co Ferritic Heat-Resistant Steel after Isothermal Aging

Qiuzhi Gao; Yanan Zhang; Hailian Zhang; Huijun Li; Fu Qu; Jian Han; Cheng Lu; Bintao Wu; Yao Lu; Yan Ma

doi:10.1038/s41598-017-06191-2

Scientific Reports (Jul 2017)

Precipitates and Particles Coarsening of 9Cr–1.7W–0.4Mo–Co Ferritic Heat-Resistant Steel after Isothermal Aging

Qiuzhi Gao,
Yanan Zhang,
Hailian Zhang,
Huijun Li,
Fu Qu,
Jian Han,
Cheng Lu,
Bintao Wu,
Yao Lu,
Yan Ma

Affiliations

Qiuzhi Gao: School of Materials Science and Engineering, Northeastern University
Yanan Zhang: Research and Development Department, CITIC Bohai Aluminium Industries Holding Company, LTD.
Hailian Zhang: School of Economics and Management, Yanshan University
Huijun Li: School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong
Fu Qu: School of Materials Science and Engineering, Northeastern University
Jian Han: School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong
Cheng Lu: School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong
Bintao Wu: School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong
Yao Lu: School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong
Yan Ma: School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong

DOI: https://doi.org/10.1038/s41598-017-06191-2
Journal volume & issue: Vol. 7, no. 1
pp. 1 – 11

Abstract

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Abstract The precipitates obtained by EPE technology from the 9Cr-1.7W-0.4Mo-Co ferritic heat-resistant steel subject to isothermal aging were investigated using SEM, TEM and XRD. The particle size distribution and the coarsening kinetics of M23C6 with duration of isothermal aging were also analyzed with or without consideration of Laves phase. The results show that the isolated dislocations were detected in delta ferrite interior, and the precipitates on delta ferrite and martensite boundaries are obviously larger than other locations. Fe2W-Laves phase can only be found as duration of aging time to 2000 h, and is preferential to form adjacent to M23C6 particles. The small M23C6 particles firstly coarsen, but the large M23C6 are relatively stable during short aging. The total coarsening rate of M23C6 precipitates is 9.75 × 10−28m3s−1, and the coarsening of M23C6 depends on the formation of Laves phase.

Published in Scientific Reports

ISSN: 2045-2322 (Online)
Publisher: Nature Portfolio
Country of publisher: United Kingdom
LCC subjects: Medicine; Science
Website: https://www.nature.com/srep/

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