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Published in: Journal of Materials Engineering and Performance 2/2019

03-01-2019

Effect of Friction Stir Processing on the Microstructure, Damping Capacity, and Mechanical Properties of Al-Si Alloy

Authors: H. J. Jiang, C. Y. Liu, Z. X. Yang, Y. P. Li, H. F. Huang, F. C. Qin

Published in: Journal of Materials Engineering and Performance | Issue 2/2019

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Abstract

Friction stir processing (FSP) was conducted on an Al-Si casting alloy. The Si phase and Al grains of an Al-Si casting alloy were refined through FSP. Furthermore, FSP with high rotation rate led to the precipitation of Mg and Si atoms and the formation of Mg2Si phase in the Al-Si alloy. Precipitation improved the low-strain damping capacity but deteriorates high-strain damping capacity of the FSP sample at room temperature. At low rotation rate, the FSP sample exhibited excellent high-temperature damping capacity mainly because of its fine grain structure and the low density of its pinning points. The plastic instability of the Al-Si alloy was eliminated by FSP because of the refinement of the Si phase. The increase in the strength of each FSP sample was attributed to the increase in second-phase and boundary strengthening effects. Thus, the mechanical properties and damping capacity of Al-Si were enhanced after FSP.

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Metadata
Title
Effect of Friction Stir Processing on the Microstructure, Damping Capacity, and Mechanical Properties of Al-Si Alloy
Authors
H. J. Jiang
C. Y. Liu
Z. X. Yang
Y. P. Li
H. F. Huang
F. C. Qin
Publication date
03-01-2019
Publisher
Springer US
Published in
Journal of Materials Engineering and Performance / Issue 2/2019
Print ISSN: 1059-9495
Electronic ISSN: 1544-1024
DOI
https://doi.org/10.1007/s11665-018-3844-2

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