Monotonic and cyclic stress-strain behaviour of a structural steel

The stress--strain behaviour of a C--Mn steel under two different microstructural conditions was studied. The analysis is carried out using models for linear and parabolic hardening. The material in the ferrite--pearlite microstructural condition shows cyclic hardening behaviour, while in the ferrite--bainite condition it exhibits cyclic softening behaviour. Hardening well above the yield point in both microstructures follows a parabolic and linear relationship between flow stress and shear strain under monotonic and cyclic loading, respectively.