Tool ceramics based on Al sub(2)O sub(3)-ZrO sub(2)-TiCN composite

Oxide composite Al sub(2)O sub(3)-ZrO sub(2)(Y sub(2)O sub(3)) powders containing 50 and 70 vol.% Al sub(2)O sub(3), are deposited from salt solutions. The surface area of the deposited powders exceeds 75 m super(2)/g. It is established that the alpha -Al sub(2)O sub(3) and t-ZrO sub(2)(Y sub(2)O sub( 3)) matrix has an effect on stepwise crystallization of alpha -Al sub(2)O sub(3) and the powder production history on the sinterability of oxide composites. Ceramics based on Al sub(2)O sub(3)-ZrO sub(2)(Y sub(2)O sub(3)) composite powder containing 20 vol.% titanium carbonitride are hot pressed to be used as a cutting tool. The microstructure and mechanical properties of the ceramics are analyzed. The best mechanical properties are shown by ceramic samples sintered at 1550 degree C at 35 MPa: bending strength 950 MPa, fracture toughness 10.1 MPa m super(1/2), and hardness 18.0 GPa. The performance and lifetime of cutting tools based on these ceramics are tested according to GOST 26613-85.