Design a Ti6Al4V–Ti43Al9V laminated composite with high strength and fracture toughness

A novel Ti6Al4V–Ti43Al9V metal-intermetallic-laminated (MIL) composite was successfully fabricated using hot-pack rolling. The microstructure and mechanical properties of the composites were also investigated. The microstructure observation showed that the composite exhibited a low extent of dynamic recrystallization (DRX), the acicular α2 phase was precipitated in the interfacial region and the γ phase was elongated along the rolling direction. This unique microstructure enables the composite to simultaneously achieve high strength and fracture toughness. The enhanced tensile strength was attributed to the defect-free interfacial region and the low extent of DRX in the composite. The composite was toughened by crack bridging, crack deflection, the acicular α2 phase precipitated in the interfacial region, and the elongated γ phase. •The Ti–TiAl MIL composite was successfully fabricated by hot-pack rolling.•The Ti–TiAl MIL composite showed an anisotropic microstructure.•The low extent of DRX in TiAl alloy improved the tensile strength of composite.•The anisotropic γ phase of TiAl alloy improved the fracture toughness of composite.