Investigation on the dynamic fracture behavior of A508-III steel based on Johnson–Cook model.

In this study, the Johnson–Cook constitutive and failure model parameters of A508-III steel are determined through quasi-static and dynamic tensile and fracture tests. The reliability of model parameters is then verified by dynamic fracture tests at different loading rates. Using the Johnson–Cook model, the dynamic fracture behavior of the SEB specimen of A508-III steel under various loading rates and geometric configurations has been simulated. The effect of loading rate and specimen geometric configuration on the dynamic fracture toughness of A508-III steel is investigated. The results reveal that the critical fracture force and impact absorbed energy increase with the increase of loading rate. The dynamic fracture behavior of deep-cracked specimens is more sensitive to the loading rate than that of shallow-cracked specimens. Moreover, the critical fracture force and impact absorbed energy increase linearly with increasing specimen thickness while the initial crack size remains constant. [ABSTRACT FROM AUTHOR]