Improved Method Used to Investigate the Dynamic Shear Failure of AISI 1045 Steel Cylinder Under Blast Loading

This study describes an improved method used to determine the dynamic shear failure of materials under blast loading conditions. The proposed method is a convenient and effective and generates material failure along the controlled fracture trajectories under uniform uniaxial stress conditions at a strain rate of 10(4) s(-1) to 10(5) s(-1). The method was developed by performing experiments on AISI 1045 steel with heat treatment. Specimens were filled with composition B explosives and detonated, and fragments were recovered. Most of the macroscopic shear cracks originated at the notch tips and connected adjacent internal and external notches. The phenomena of multipath and bifurcate shear fracture trajectories were also observed. Fractography analysis of the fragments provided data on damage and failure mechanism and revealed that dynamic shear fracture was characterized by microvoids and microcracks. The adiabatic shear band of AISI 1045 steel was detected on the fracture surface boundary. This finding indicates that adiabatic shear localization is the underlying failure mechanism of the studied material.