Interface formation of TiNif/Al composites fabricated by spark plasma sintering

Aluminum matrix composites reinforced by TiNi fibers were fabricated using spark plasma sintering (SPS). The characteristics and formation of the interface between the fibers and matrix were investigated. Microstructural observation indicated the interface exhibits bilayer features. The layer close to the fiber consisted of a multiple phase mixture, with a typical thickness of about 1 μm, and its formation was proved in the initial stage and related with the local melting phenomenon in contact zones during SPS. The other layer exhibited a periodic morphology resulting from the alternating phases of Al3Ti and Al3Ni, and a qualitative model describing the formation of such a layered structure was proposed.