Effect of Interface on Mechanical Properties and Stamping Formability of Ti/Al Multilayered Composites

Ti/Al multilayered composites (LMCs) with 3-layers, 5-layers and 7-layers were prepared by hot‐pressing and hot‐rolling. The effects of the interface on the mechanical properties and stamping formability of LMCs were revealed. The results indicate that the TiAl₃ phases at the interface thicken gradually with the increase of layers. As the layers of LMCs increases, both the grain size and the basal texture strength of Ti decrease, and Ti possesses a higher Schmid factors (SF) and more uniform SF distribution, which promotes the overall coordinated deformation of LMCs. The elongation (EL) of LMCs gradually increases at the expense of the strength with the increase of layers. The stress–strain transfer across the interface, the release of residual stress through interfacial microcracks, and the improvement of the interfacial metallurgical bonding strength are all conducive to the coordinated deformation between Ti and Al layers, thus the strength of LMCs decreases and the EL enhances. Both the yield strength ratio (σ_s/σ_b) and plastic strain ratio (r) decrease, while the strain-hardening exponent (n) increases with the increase of layers of LMCs, which are beneficial to improve the stamping formability of LMCs. The number of interface increases with the increase of layers, which hinders crack propagation. Moreover, the microcracks are easily induced by the brittle TiAl₃ phase at the interface, and the main cracks deflect obviously and release part energy in the form of secondary microcracks, thus delaying the failure of LMCs and improving their stamping formability.