Preparation and mechanical properties of Al₇₂Ni₁₂Co₁₆/A365 quasicrystal particle reinforced Al matrix composites

Al matrix composites withAl₇₂Ni₁₂Co₁₆ particles of volume fraction ranging from 5 %～20 % were prepared. The quasicrystal material was obtained by casting Al₇₂Ni₁₂Co₁₆ alloy on the water cooling copper subst rate. TEM and X-ray diffraction analysis indicate that the obtained material is single-phase quasicrystal material. Most defects of as-cast composites are eliminated by the hot extrusion, and the mechanical property test reveals that with addition ofAl₇₂Ni₁₂Co₁₆, the tensile strength, yield strength and elastic modulus of Al matrix composites increase remarkably from 275 MPa, 200 MPa and 70 GPa to 410 MPa, 350 MPa and 102 GPa,respectively; on the other hand, the elongation decreases from 6 % to 3 %. Based on the above experiment, the fracture mechanism and strengthening mechanism were discussed in detail .