Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5459196 | Journal of Alloys and Compounds | 2017 | 11 Pages |
Abstract
A fine-grained Al-6.10%Mg-0.30%Mn â0.25%Sc-0.1%Zr (wt. %) alloy with an average grain size of â¼1.10 μm was subjected to an improved asymmetrical rolling (ASR) process. Superplastic behavior of the asymmetrical rolled alloy was investigated at 450-500 °C and strain rate range of 5 Ã 10â3 sâ1 to 2.5 Ã 10â1 sâ1. It is indicated that the asymmetrical rolled alloy exhibited excellent superplasticity (elongations of >1000%) at high strain rates ranging from 1 Ã 10â2 sâ1 to 2.5 Ã 10â1 sâ1, and maximum elongation of â¼3170% was obtained at 500 °C and a high strain rate of 5 Ã 10â2 sâ1. The microstructural results showed that the shear components and the β-fiber rolling texture gradually transferred into a random texture, and LABs progressively changed to HABs during deformation. Such a microstructure can accelerate the cooperative grain boundary sliding leading to a higher superplasticity. Further, superior superplastic behavior of the asymmetrical rolled alloy can be ascribed to the fine (sub)grains which may slow down the rate of cavity growth and the stable coherent Al3(Sc1-xZrx) nano-particles that can ensure a good stability of the fine-grained structure during superplastic deformation. Analyses on superplastic data and microstructure characteristic revealed that grain boundary sliding might be the main deformation mechanism during deformation.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Yulu Duan, Guofu Xu, Lei Tang, Yun Liu, Jiawei Xu, Ying Deng, Zhimin Yin,