NOVEL ALUMINA TITANIUM-CARBONITRIDE NICKEL COMPOSITES

Alumina-containing titanium-carbonitride nickel composites (Al2O3-TiCN -Ni-Mo2C) have been synthesized with up to 20 vol.% alumina particles and nickel con ten ts of 10-15 vol.%. Alumina in the form of platelets as well as powders have been successfully incorporated into the compo sites. The mechanical properties of these composites show a marked inc rease in toughness while retaining a good hardness and a low density w hen compared to TiCN-Ni cemented carbides. The presence of alumina wit h its superior chemical and wear resistance makes these composites ver y attractive for all wear parts-particularly for pieces exposed to che mically aggressive environments and high-temperature applications. Mor eover, the complementary properties of these new composites (e.g., lig ht weight, hardness, toughness, and chemical stability) allow a wide r ange of applications to be envisaged.