Plastic deformation of Al13Fe4 particles in Al–Al13Fe4 by high-speed compression

Spray-formed Al–Fe alloys having undergone high-speed deformation were examined under a high-voltage electron microscope. Two types of specimens were examined; one containing fine Al13Fe4 particles, and the other containing large particles. In the former specimen, deformation is found to proceed in three patterns, depending on specimen thickness and strain rate: (1) without deformation of the Al13Fe4; (2) breaking of the Al13Fe4; or (3) melting of the Al13Fe4. Local melting is found to alter some of the Al13Fe4 particles, to impart five-fold symmetry in diffraction or an amorphous structure. In the latter specimen, introduction of glide dislocations enabled us to determine a shear system in the mc102 monoclinic c2/m crystal of Al13Fe4. On the bases of these observations, the mechanism of high-speed deformation is discussed while taking into account the highly stressed and/or heated states of Al13Fe4 embedded in Al matrix.