Interface tensile and fracture behavior of the Ti/Al3Ti Metal-Intermetallic Laminate (MIL) composite under quasi-static and high strain rates

A novel specimen was designed to study the interface tensile behavior and fracture mechanism of the Ti/Al3Ti Metal-Intermetallic Laminate (MIL) composite under quasi-static and high strain rates. The experimental results indicated that the interface tensile strength of the Ti/Al3Ti MIL composite increases with increasing strain rate. The fracture mechanisms of the Ti/Al3Ti MIL composite are different under quasi-static (~0.001/s) and high strain (~300/s) rates. Generally, fracture only occurs in the interface under quasi-static tensile condition, while the fracture is also found in Al3Ti layer apart from the interface under high strain rate. The quasi-cleavage features are visible in the interface surface of Ti layer in both quasi-static and high strain rates. Moreover, large dimples are found in the fracture surface under high strain rate, and the tearing ridges are more than that under quasi-static strain rate. The brittle Al3Ti layers show an intergranular fracture behavior, along with minor transgranular fractures and secondary micro-crack formed in the grain boundary.