Achieving high combination of strength and ductility of Al matrix composite via in-situ formed Ti-Al₃Ti core-shell particle

In this work, a new tactic was proposed to fabricate Ti-Al₃Ti core-shell particles reinforced Al matrix composites. Full densification of composites was realized by spark plasma sintering followed by hot rolling. Formation of Ti-Al₃Ti core-shell particles was achieved by controlling the in-situ reaction between Al matrix and Ti particles during post annealing process. The obtained results show that such in-situ formed core-shell particles with a proper thickness of Al₃Ti shell not only have strong interfacial bonding with Al matrix for effective load transfer, but also delay the composite fracture by inhibition of crack propagation, resulting in well balanced tensile strength (~ 241 MPa) and ductility (~ 19.8%). This work provides a new way to achieve high combination of strength and ductility of metal matrix composites for engineering application.