Constitutive equation and microstructure analysis of Al_0.6CoCrFeNi high entropy alloy during hot deformation

ABSTRACT

The hot deformation behaviour of Al_0.6CoCrFeNi high entropy alloy during isothermal hot compression was studied at 950–1100°C and 0.001–1 s⁻¹. The high-temperature constitutive equation of this alloy is established based on the Arrhenius type equation to explore relationship between flow stress and strain, temperature and strain rate. The hot deformation microstructure was characterised by optical microscope (OM) and electron backscatter diffraction (EBSD). The results show the constitutive equation based on the Arrhenius type considering strain compensation has a good prediction precision with an average absolute relative error of 7.9%. During hot deformation, the softening mechanisms are mainly dynamic recovery (DRV), continuous dynamic recrystallisation (CDRX), and discontinuous dynamic recrystallisation (DDRX). And the FCC phase texture has a higher intensity than the BCC phase texture.

KEYWORDS:

• High entropy alloy
• flow stress
• constitutive equation
• microstructure

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors are very grateful for the support received from Innovation and Entrepreneurship Training Program for university students [grant numbersS202113679009 and Y202113679007].