Even though Al2O3 material having high hardness reduces wear debris materials, it cannot satisfy the properties of prosthetichip or knee join replacements because of its low fracture toughness. Thus, bearing materials in prosthetic hip or knee jointreplacements basically require high hardness and high fracture toughness. To improve their mechanical properties (hardnessand fracture toughness), the approach commonly utilized has been the addition of a second phase to form a composite andproduce nanostructured materials. The nanopowders of CoAl and Al2O3 were synthesized from Co3O4 and Al powders by highenergy ball milling. The nanostructured 2.25CoAl-Al2O3 composite from the milled powder was densificated within a shorttime by the high frequency induction heated sintering. The mechanical properties of the nanostructured 2.25CoAl-Al2O3 werehigher than those of monolithic CoAl and Al2O3, respectively. And the composite was evaluated as excellent biocompatibility

Keywords: Composite, Nanostructure, Mechanical properties, Sintering, Powder processing