A novel (AlN + Si3N4)/Al composite with well-balanced strength and ductility

A novel aluminum matrix composite reinforced by AlN and Si3N4 particles was prepared. It is found that the mean sizes of AlN and Si3N4 particles which distribute uniformly in the α-Al matrix, are 50 nm and 0.5 µm, respectively. The as-extruded composite presents a sheet texture of {110}< 111 >, and the mean size of the α-Al grains at the longitudinal section is 1.14 µm measured by electron backscatter diffraction (EBSD). After T4 heat treatment, the orientation of the α-Al grains has evolved and their mean size decreases to 0.63 µm, which is ascribed to the recrystallization process. The composite exhibits excellent mechanical properties of well-balanced strength and ductility, which can be up to 425 MPa and 15.5%, respectively.