Ratcheting strain in interstitial free steel

This investigation illustrates ratcheting phenomenon, in-situ substructural variations during ratcheting and post-ratcheting tensile properties of interstitial free steel at ambient temperature (approximate to 300 K). The results highlight that the nature of strain accumulation is dependent on the magnitude of the employed combinations of mean stress (sigma(m)) and stress amplitude (sigma(a)); this phenomenon has been explained considering the asymmetry of loading cycles and substructural variations as delineated by TEM. Tensile strength increases while ductility decreases for ratcheted samples with increasing sigma(m) and/or sigma(a) and these variations in tensile properties are correlated with the induced cyclic hardening. (C) 2013 Elsevier B.V. All rights reserved.