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Extraordinary Superplastic Ductility of Magnesium Alloy ZK60

Published online by Cambridge University Press:  01 June 2005

R. Lapovok*
Affiliation:
School of Physics and Materials Engineering, Monash University, Victoria 3800, Australia
R. Cottam
Affiliation:
School of Physics and Materials Engineering, Monash University, Victoria 3800, Australia
P.F. Thomson
Affiliation:
School of Physics and Materials Engineering, Monash University, Victoria 3800, Australia
Y. Estrin
Affiliation:
Institut für Werkstoffkunde und Werkstofftechnik, TU Clausthal, 38678 Clausthal-Zellerfeld, Germany
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Exceptionally high tensile ductility of commercial Mg alloy ZK60 is reported. It was achieved by equal channel angular pressing without any extra processing steps. The tensile ductility at 220 °C was 2040% and 1400% for the strain rates of 3 × 10−4 s−1 and 3 × 10−3 s−1, respectively. The strain rate sensitivity of the flow stress exhibited a value slightly above 0.5, which is characteristic of superplastic deformation. The grain structure associated with this behavior was shown to be bi-modal with further separation in two fractions with different grain sizes within the small grain size population.

Type
Rapid Communications
Copyright
Copyright © Materials Research Society 2005

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References

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