The Elastic Effect of Evolving Precipitate Shapes on the Ripening Kinetics of Tetragonal Phases

DOI zum Zitieren der Version auf EPub Bayreuth: https://doi.org/10.15495/EPub_UBT_00007035
URN to cite this document: urn:nbn:de:bvb:703-epub-7035-2

Title data

Schleifer, Felix ; Lin, Yueh-Yu ; Glatzel, Uwe ; Fleck, Michael:
The Elastic Effect of Evolving Precipitate Shapes on the Ripening Kinetics of Tetragonal Phases.
In: Metallurgical and Materials Transactions A. Vol. 54 (2023) Issue 5 . - pp. 1843-1856.
ISSN 1543-1940
DOI der Verlagsversion: https://doi.org/10.1007/s11661-022-06877-x

	Format: PDF Name: s11661-022-06877-x.pdf Version: Published Version Available under License Creative Commons BY 4.0: Attribution
	Download (3MB)

Project information

Project financing:	Deutsche Forschungsgemeinschaft

Abstract

Coherent tetragonal precipitates, such as the Ni3Nb phase γ″ found in Ni-base superalloys, appear as plate-shaped particles. These shapes are the result of anisotropic elastic misfit strains. We present 3D sharp phase-field simulations that capture this circumstance well due to the inclusion of the elastic effects from the misfit. These simulations reveal that the ripening behavior of γ″ precipitates deviates significantly from the classical LSW theory of Ostwald ripening. A ripening exponent of 2 rather than 3 describes the simulated γ″ size evolution at temperatures between 700 °C and 760 °C best. Employing a quantitative distinction argument, we show that 60 pct of this deviation is attributed to the elastically induced size dependence of the precipitate shapes. With increasing precipitate size, the minimization of elastic energy leads to steadily increasing plate aspect ratios. The precipitate ripening kinetics accelerate with increasing aspect ratio. Fitting the newly received square root time dependence to experimental data yields a physically conclusive activation energy of ripening close to the activation energy of Nb diffusion in the alloy.

Further data

Item Type:	Article in a journal
DDC Subjects:	600 Technology, medicine, applied sciences > 620 Engineering
Institutions of the University:	Faculties > Faculty of Engineering Science > Chair Metals and Alloys > Chair Metals and Alloys - Univ.-Prof. Dr.-Ing. Uwe Glatzel Faculties Faculties > Faculty of Engineering Science Faculties > Faculty of Engineering Science > Chair Metals and Alloys
Language:	English
Originates at UBT:	Yes
URN:	urn:nbn:de:bvb:703-epub-7035-2
Date Deposited:	12 Jun 2023 09:19
Last Modified:	12 Jun 2023 09:20
URI:	https://epub.uni-bayreuth.de/id/eprint/7035

Download Statistics

Download Statistics

Download Statistics

Downloads

Downloads per month over past year