Mechanism of Low-Temperature Superplastic Deformation in Aluminum Alloys Containing a Dispersion of Nanoscale Al3(Sc,Zr) Particles


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The ultrafine grained (UFG) structure with an average size of ∼0.8 μm was produced in an Al-Li-Mg-Sc alloy by equal-channel angular extrusion (ECAE) at 325oC with a total strain of ~16. Superplastic behavior was examined in the temperature range 150-250oC at strain rates ranging from 10-5 to 10-2 s-1. A maximum elongation-to-failure of 440% was recorded at 175oC (~0.5 Tm, where Tm is the melting point) and a strain rate of 2.8×10-5 s-1 with the corresponded strain rate sensitivity coefficient of 0.32. Mechanisms of low-temperature superplasticity (LTSP) and high-strain-rate superplasticity (HTSP) are essentially the same. The difference between superplastic behaviors at low and high temperatures is attributed to applied stress.



Materials Science Forum (Volumes 838-839)

Edited by:

Eiichi Sato, Goroh Itoh, Yoshimasa Takayama, Koichi Kitazono, Koji Morita, Takaomi Itoi and Junya Kobayashi




R. Kaibyshev, "Mechanism of Low-Temperature Superplastic Deformation in Aluminum Alloys Containing a Dispersion of Nanoscale Al3(Sc,Zr) Particles", Materials Science Forum, Vols. 838-839, pp. 150-156, 2016

Online since:

January 2016





* - Corresponding Author

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