Nanometer Al₂O₃-Cu composites with high plasticity and strength

Using water-atomized Cu-Al alloy powder as raw materials,Al₂O₃ dispersion-strengthened copper composite materials were fabricated by the internal oxidation method.The obtained composite materials were comprehensively characterized by field emission scanning electron microscopy (FE-SEM) and X-ray diffraction analysis.The results show that γ-Al₂O₃ nano-particles with a mean size of 6 nm are uniformly distributed in the matrix and the space distance between particles is about 30 to 50 nm.The conductivity of the hot extruded bars is 87% IACS and the softening point is 850℃.Without any intermediate heat treatment,copper wires of Ф1 mm in diameter were produced by direct cold drawing from the dispersion-strengthened copper bars of Ф25 mm in diameter.The tensile strength of these copper wires is 680 MPa.