Coating Cu nano-sized particles on Al2O3 powders by a wet-chemical method and its mechanical properties after hot press sintering

Cu-coated Al2O3 powders were prepared by the heterogeneous method starting with Al2O3 and CuSO4·5H2O raw materials. Nanometer Al particles were used to reduce Cu resulting in a uniform coating of Cu particles on the Al2O3 grains. TEM, XRD and XPS were used to analyses the status of the nano-sized Cu particles on the surface of Al2O3 grains. The mechanical properties of the composite were investigated after hot press sintering at different temperatures. Samples with enhanced fracture toughness about 5.75 MPa m1/2 were obtained after hot press sintering at temperature 1500 °C, which is much higher than that of monolithic Al2O3 ceramics.