Design of (Hf,Ta)Fe2/Fe composite with zero thermal expansion covering room temperature

SCRIPTA MATERIALIA

卷:186

Article

Cen, Dongyu¹  Wang, Bin¹  Chu, Ruixue¹  Gong, Yuanyuan¹  Xu, Guizhou¹  Chen, Fenghua^2,3  Xu, Feng¹ 

[1] Nanjing Univ Sci & Technol, MIIT Key Lab Adv Met & Intermet Mat Technol, Nanjing 210094, Peoples R China

[2] Taiyuan Univ Sci & Technol, Coll Mat Sci & Engn, Taiyuan 030024, Peoples R China

[3] Univ Wollongong, Sch Mech Mat Mechatron & Biomed Engn, Wollongong, NSW 2522, Australia

关键词: zero thermal expansion;    magnetic phase transition;    Hf1-xTaxFe2 compounds;    negative thermal expansion;   

DOI  :  10.1016/j.scriptamat.2020.05.048

来源: Elsevier

【 摘 要 】

MgZn2-type (Hf,Ta)Fe-2 is a typical negative-thermal-expansion system, which expands during the establishment of ferromagnetic ordering in cooling. This abnormal behavior suggests that (Hf,Ta)Fe-2 is a potential ingredient to produce a composite with zero thermal expansion. In this work, we find that the as-cast (Hf,Ta)Fe-2 have Fe-rich grain boundaries, which disappear after annealing. It inspires us to produce a (Hf,Ta)Fe-2/Fe composite by adding extra Fe in nonstoichiometric composition without annealing. After carefully tuning Hf/Ta ratio and Fe concentration, room-temperature zero-thermal-expansion is achieved in the sample with a composition of Hf0.80Ta0.20Fe2.5. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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