In situ transmission electron microscopy investigation of continuous precipitation of Ni3Mo in a superalloy formed by direct current magnetron sputtering

SCRIPTA MATERIALIA

卷:173

Article

Emigh, Megan G.^1,2  Krogstad, Jessica A.¹ 

[1] Univ Illinois, Dept Mat Sci & Engn, 1304 W Green St, Urbana, IL 61801 USA

[2] Univ Illinois, Mat Res Lab, 104 S Goodwin Ave, Urbana, IL 61801 USA

关键词: Precipitation;    Transmission electron microscopy;    Nickel alloys;    Lattice defects;    Phase transformation kinetics;   

DOI  :  10.1016/j.scriptamat.2019.07.028

来源: Elsevier

【 摘 要 】

In situ heating experiments explore a correlation between hexagonal close-packed (HCP) domains in sputter-deposited Ni-25Mo-8Cr films and the precipitation of HCP-type structures (Ni3Mo). Dynamic observation of phase evolution in diffraction mode confirms that precipitation behavior in these defect-dense thin films is not merely kinetically accelerated; instead, the pathway is fundamentally altered. Short-range ordering (SRO) behavior was observed upon reaching 650 degrees C. SRO has been documented as part of the face-centered cubic (FCC)-precipitation pathway, but has not previously been reported for HCP-based precipitates. This effort provides evidence for continuous ordering of HCP-based precipitates from SRO domains in a mixed FCC-HCP metallic material. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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