Aluminum composites reinforced by γ-graphynes: The effect of nanofillers porosity and shape on crystal growth and composite strengthening

Graphyne and graphdiyne nanofillers (nanoplatelets and nanotubes), are embedded in Aluminum matrices originating graphyne and graphdiyne/Al nanocomposites. Pristine Al and the nanocomposites are melted and then recrystallized at a fixed colling rate, 1 K/ps. Al nanocomposites with planar nanofillers show a 46-53% increase in nucleation temperature and 78-88% recrystallization yield while Al nanocomposites with tubular nanofillers present a 16-32% increase in nucleation temperature and a 65-75% recrystallization yield. Al nanocomposites with planar nanofillers present a 26-36% increase in the Young's modulus, while Al nanocomposites with tubular nanofillers show a 23-31% increase in the Young's modulus. The improved mechanical properties of graphyne and graphdiyne/Al nanocomposites depend on i) the elasticity and shape (planar vs tubular) of the nanofillers ii) the level of recrystallization of the Al matrix and iii) the interfacial adhesion in the interface between the nanofillers and the Al matrix. Graphyne pore size positively affects interfacial adhesion.