Influences of cell walls and grain boundaries on transient responses of an if steel to changes in strain path

doi:10.1016/0956-7151(94)90127-9

Acta Metallurgica et Materialia

Volume 42, Issue 4, April 1994, Pages 1099-1111

https://doi.org/10.1016/0956-7151(94)90127-9 Get rights and content

Abstract

The effects of changes in strain path on plastic behaviour in sheets of an interstitial-free steel with two widely different grain sizes were investigated. The sheets were prestrained in rolling and, apart from supplementary tests, they were tested in uniaxial tension at 90° to the rolling direction. The results support the following conclusions. The magnitude of the increase in reloading yield stress and amplitude of the subsequent reduction in work hardening depend on the strength of dislocation walls generated in the prestrain rather than the grain size. The walls are more effective barriers to dislocation glide in freshly activated slip systems than to glide in the original slip systems operating in the prestrain. The primary cause of the subsequent reduction in hardening rate is disruption and partial dissolution of the original dislocation substructure. The final recovery in hardening rate is caused by generation of a new substructure compatible with the new deformation mode.

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Influences of cell walls and grain boundaries on transient responses of an if steel to changes in strain path

Abstract

J. Mech. Phys. Solids

Metall. Trans.

Metall. Trans.

Mater. Sci. Engng

Mater. Sci. Engng

Acta metall.

Acta metall. mater.

Mater. Sci. Engng

Acta metall.

Acta metall.

Acta metall.

Metall. Trans.