Mixed Mode (Mode I/III) Dynamic Fracture Initiation Toughness of Aluminum Alloy

摘要

In this study, a hybrid experimental-numerical approach is used to determine the mixed mode (mode I/III) dynamic fracture initiation toughness of aluminum alloy. Cylindrical specimens with spiral v-notch at a revolution angle of 360° and pitch angles 22.5° (inclined angles) are fabricated from aluminum rod. A torsional Hopkinson bar apparatus is used to generate and apply a dynamic torsional load on the specimens. A stereo digital image correlation is used to measure full-field displacements around the crack tip and to estimate the fracture initiation time. A commercial finite element software (ABAQUS) is used to extract a dynamic stress intensity factors based on interaction integral method. The stress distribution, full-field deformation with time, and the mixed mode fracture toughness are discussed.