Microstructure and Mechanical Properties of Bio-Inspired Ti/Al/Al-C _f Multilayered Composites

In this work, a novel Ti/Al/Al-C _f multi-layered composite consisted of periodically alternating brittle and ductile layers has been successfully fabricated through the biological shell structure consideration as the prototype. Pure titanium foils (Ti), aluminum foils (Al), and woven C fibers (C _f ) with Ni coating are adopted and stacked in a specific order, namely the Ti, Al, C _f , and Al order. The results demonstrated that all layers are well bonded. The Al ₃ Ti and Al ₃ Ni phases are formed at the Ti/Al and C _f /Al interface, respectively. Compression and three-point bending tests are conducted to investigate the mechanical properties of the bio-inspired composites. Due to the special layered structure and reinforcing effect of the C _f , the novel material has high compressive strength (565 MPa), as well as high bending strength (413 MPa). It is discovered that the hierarchical structure can effectively delay crack propagation and absorb energy during fracture. The authors’ work provided new sight for the design of a new bio-inspired composite and better understanding the relationship of mechanical performance and hierarchical structure.