In-situ observation of crack initiation and propagation in Ti/Al composite laminates during tensile test

The main aim of this work is to explore and analyze the crack initiation and propagation in Ti/Al composite laminates during the in-situ tensile test. The Ti/Al composite laminates were fabricated using explosive welding method, and the morphology and elemental distribution of the bonding interface were then investigated by means of SEM and EDS. Subsequently, in-situ tensile test results showed that the intermetallic compounds could form at the interface of Ti/Al composite laminates, and also could easily induce the initiation of microcrack under tensile forces. Furthermore, the microcracks almost propagated along the 45° angle with the tensile direction to Ti layer rather than Al layer. These features of microcracks mainly attributed to the hard and brittle phase (TiAl3) and the plasticity distinction between Ti and Al metals. Finally, the fracture mechanism was mainly about the crack initiation and the stress concentration in the Ti/Al composite laminates.