Flow stress equation for multipass hot-rolling of aluminum alloys

Abstract

A series of simple axisymmetric compression tests were carried out on the computer servo-controlled Gleeble 1 500 machine when strain rates ranged between 0.05–25 s⁻¹ and deformation temperature 300–500 °C. The results show that flow stress is related to the Zener-Hollonom parameter Z and strain, as well as the static recrystallization fraction between passes during multipass hot deformation of 5182 aluminum alloy. Hence, a modified exponential flow stress equation was presented by considering the values of InA and β as functions of strain, and by using the uniform softening method and incorporating the static recrystallization fraction between passes to consider the effects of residual strain during multipass hot-rolling of 5182 aluminum alloy. The validity of the equation was examined by a typical non-isothermal multipass deformation test.

Keywords

5182 aluminum alloy / multipass hot-rolling / flow stress equation

References

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