Superplasticity of AlCoCrCuFeNi High Entropy Alloy

Abstract:

An AlCoCrCuFeNi high entropy alloy was multiaxially isothermally forged at 950°C to produce a fine equiaxed structure with the average grain/particle size of ~1.5 µm. The forged alloy exhibited superplastic behavior in the temperature range of 800-1000°C. For example, during deformation at a strain rate of 10-3 s-1, tensile ductility increased from 400% to 860% when the temperature increased from 800°C to 1000°C. An increase in strain rate from 10-4 to 10-2 s-1 at T = 1000°C did not affect ductility: elongation to failure was about 800%. The strain rate sensitivity of the flow stress was rather high, m = 0.6, which is typical to the superplastic behavior. The equiaxed morphology of grains and particles retained after the superplastic deformation, although some grain/particle growth was observed.

• Periodical: Materials Science Forum (Volume 735)
• Pages: 146-151
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.735.146
• Online since: December 2012
• Authors: Andrey V. Kuznetsov, Dmitry G. Shaisultanov, Nikita Stepanov, Gennady A. Salishchev, Oleg N. Senkov
• Keywords: High Entropy Alloy, Microstructure, Multi-Directional Forging, Superplasticity

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DOI: 10.1007/s10853-012-6260-2

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