Effect of Temperature on the Superplasticity of AZ81 Magnesium Alloy Processed by Hot Extrusion

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An AZ81 magnesium alloy, which was processed by hot extrusion in advance, was tested in the temperature range of 473 ~ 623 K and at various initial strain rates, ranging from 1×10-1 to 1×10-4 s-1. True stress-true strain curves under various temperatures and activation energy within different temperature range were investigated for the analysis of effect of temperature on superplastic behaviors. Elongation of the as-extruded AZ81 alloy increased with temperature when tested at the same initial strain rate. Elongation values, obtained at the same initial strain rate of 1×10-3 s-1, were 94% at 473K and 446% at 623K, respectively. Deformation mechanisms varied with increasing temperature, from the grain boundary sliding (GBS) accommodated by grain boundary diffusion to the GBS accommodated by lattice diffusion, transition temperature was 573 K.

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Periodical:

Materials Science Forum (Volumes 488-489)

Edited by:

W.Ke, E.H.Han, Y.F.Han, K.Kainer and A.A.Luo

Pages:

585-588

Citation:

L. Lin et al., "Effect of Temperature on the Superplasticity of AZ81 Magnesium Alloy Processed by Hot Extrusion", Materials Science Forum, Vols. 488-489, pp. 585-588, 2005

Online since:

July 2005

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$38.00

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