Applications of Neuber’s and Glinka’s notch plasticity correction rules to asymmetric magnesium alloys under cyclic load

Abstract

The asymmetric cyclic behaviour of rolled ZEK100-F magnesium alloy has been considered, while approximating its notch stress-strain response through applying Neuber’s and Glinka’s rules. To this end, a numerical procedure has been developed and scripted in Matlab that makes use of a hysteresis regeneration model in association with plane stress/strain notch approximate rules as well as Smith-Watson-Topper (SWT) fatigue model. Output from the Matlab routine in terms of notch root strain estimations are validated using constant and variable amplitude load-controlled cyclic experimental results, obtained via digital image correlation (DIC) technique, on ZEK100-F plate specimens with a central circular hole. Glinka’s rule is shown to give comparatively closer approximations. Applying Glinka’s rule, further validation of modelled notch response is adequately done by estimating fatigue life based on SWT parameter and comparing it with DIC-measured crack initiation life.