Segregation assisted microtwinning during creep of a polycrystalline L1(2)-hardened Co-base superalloy
Freund L, Messe OMDM, Barnard JS, Göken M, Neumeier S, Rae CMF (2017)
Publication Status: Published
Publication Type: Journal article
Publication year: 2017
Journal
Publisher: PERGAMON-ELSEVIER SCIENCE LTD
Book Volume: 123
Pages Range: 295-304
DOI: 10.1016/j.actamat.2016.10.048
Abstract
A polycrystalline L1(2)-hardened Co-base superalloy was creep deformed at 750 degrees C. The investigation of the deformed microstructure in the transmission electron microscope revealed microtwinning to be the prevailing deformation mechanism. The detected twins spanned the entire grain and cut through both, gamma and gamma'. Detailed high-resolution transmission electron microscopy investigations indicated that twin growth takes place by the slip of single a/6 (112) partial dislocations along the twin boundary. Further analysis of the twin boundaries in the gamma' phase revealed segregation of elements known to decrease the stacking fault energy and a local depletion of gamma' forming elements. We propose that this segregation behavior enables subsequent a/6 < 112 > dislocations to easily slip along the twin boundary and further thicken the twins in the process. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Authors with CRIS profile
Lisa Freund
Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften)
Mathias Göken
Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften)
Steffen Neumeier
Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften)
Additional Organisation(s)
Related research project(s)
A06 (FP3): Miko- und nanomechanische Charakterisierung von Superlegierungen bei hohen Temperaturen (SFB/TRR 103)
SFB/TRR 103
Jan. 1, 2020 - Dec. 31, 2023
GRK 1229: Stabile und metastabile Mehrphasensysteme bei hohen Anwendungstemperaturen
April 1, 2006 - March 30, 2015
Involved external institutions
United Kingdom (GB)How to cite
APA:
Freund, L., Messe, O.M.D.M., Barnard, J.S., Göken, M., Neumeier, S., & Rae, C.M.F. (2017). Segregation assisted microtwinning during creep of a polycrystalline L1(2)-hardened Co-base superalloy. Acta Materialia, 123, 295-304. https://doi.org/10.1016/j.actamat.2016.10.048
MLA:
Freund, Lisa, et al. "Segregation assisted microtwinning during creep of a polycrystalline L1(2)-hardened Co-base superalloy." Acta Materialia 123 (2017): 295-304.
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