(Al 2O 3 + Al 3Zr)/A356 nanocomposites fabricated by magnetochemistry in situ reaction

The (Al 2O 3 + Al 3Zr)/A356 nanocomposites are fabricated via magnetochemistry in situ reaction. The interface between the in situ particles and the aluminum matrix, the mechanical properties and behaviors are investigated by SEM, TEM and in situ tensile observations. The results indicate that the interfaces are net and no interfacial outgrowth observed; the values of the tensile strength, yield strength and the Brinell Hardness are reached 393.8 MPa, 339.74 MPa and 139.8 kgf/mm 2, respectively with the pulsed magnetic field assistance; the cracks are initiated by the dislocation accumulation effects, the cavity-nucleation effects and the matrix flaw effects; the crack growth behaviors are very much dependent on the microstructure of the composites. The fracture model of the composites is established and discussed.