In-situ observations of the tensile deformation and fracture behavior of a fine-grained titanium alloy sheet

Abstract Deformation and crack initiation of industrial Ti-6Al-4V titanium alloy sheet were investigated using in-situ scanning electron microscopy (SEM) at room temperature. The results showed that slip band originated from α/α and α/β interfaces when the tension reaches the yield stage, and the slip mode develops from single slip to multi slip and finally the cross-slip occurs. Microcracks initiate primarily at the phase boundary or along the slip band within α phase, cracks are mainly connected along the 45° line. The fracture surface is full of dimples. Intergranular cracking is the main fracture mechanism.