High-temperature damage-tolerance of a hot-rolled brick-and-mortar Ti₂Ni/TiNi composite

A nacre-like biomimetic Ti₂Ni/TiNi brick-and-mortar composite, consisting of brittle Ti₂Ni bricks homogeneously distributed in ductile TiNi mortars, is produced by hot rolling conventional laminated composite. When deformation temperature is between 25 and 500 °C, the brick-and-mortar composite essentially remains constants of fracture toughness (50 MPa·m^1/2) and flexural strength (1250 MPa). This is consistent with zig-zag crack trajectories inherited from the nacre-like structure, providing a strong extrinsic toughening. Further increasing the deformation temperature up to 700 °C dramatically deteriorates the flexural strength because the TiNi mortars are strongly softened. Therefore, the Ti₂Ni/TiNi brick-and-mortar composite exhibits a high-temperature damage-tolerance up to 500 °C.