Figure 5

(a) SEM micrograph of fractured surface, displaying that macroscopic crack propagates along with the boundaries of micron-sized fcc (CoFe)Ti₂ twins and nanostructured matrix or passes through micron-sized fcc (CoFe)Ti₂ twins. (b) Magnified detail information of local deformed region, presenting that the cracks were produced preferentially in fcc (CoFe)Ti₂ twins and hindered by the matrix. The inset shows that profuse of shear bands formed in the matrix and blocked by nano-sized TiFe particles, implying excellent strain-hardening capacity. (c) TEM image observed in local deformed matrix, indicating that lots of dislocations generated in β-Ti regions were blocked by TiFe particles.