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Hierarchical microstructure strengthening in a single crystal high entropy superalloy.

ABSTRACT: A hierarchical microstructure strengthened high entropy superalloy (HESA) with superior cost specific yield strength from room temperature up to 1,023 K is presented. By phase transformation pathway through metastability, HESA possesses a hierarchical microstructure containing a dispersion of nano size disordered FCC particles inside ordered L1₂ precipitates that are within the FCC matrix. The average tensile yield strength of HESA from room temperature to 1,023 K could be 120 MPa higher than that of advanced single crystal superalloy, while HESA could still exhibit an elongation greater than 20%. Furthermore, the cost specific yield strength of HESA can be 8 times that of some superalloys. A template for lighter, stronger, cheaper, and more ductile high temperature alloy is proposed.

SUBMITTER: Chen YT

PROVIDER: S-EPMC7376180 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Hierarchical microstructure strengthening in a single crystal high entropy superalloy.

Chen Yung-Ta YT Chang Yao-Jen YJ Murakami Hideyuki H Sasaki Taisuke T Hono Kazuhiro K Li Chen-Wei CW Kakehi Koji K Yeh Jien-Wei JW Yeh An-Chou AC

Scientific reports 20200722 1

A hierarchical microstructure strengthened high entropy superalloy (HESA) with superior cost specific yield strength from room temperature up to 1,023 K is presented. By phase transformation pathway through metastability, HESA possesses a hierarchical microstructure containing a dispersion of nano size disordered FCC particles inside ordered L1<sub>2</sub> precipitates that are within the FCC matrix. The average tensile yield strength of HESA from room temperature to 1,023 K could be 120 MPa hig ...[more]

PMID: 32699329

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