초록 ▼

This invention is directed to the preparation of ZrO2 bodies partially stabilized through the inclusion of 0.5-10% Y2O3 with 1-10% of a secondary stabilizer selected from the group of MgO, CaO, CuO, ZnO, and CeO2. The method comprises sintering a shaped batch at 1600°-1800°C., quickly cooling the si

This invention is directed to the preparation of ZrO2 bodies partially stabilized through the inclusion of 0.5-10% Y2O3 with 1-10% of a secondary stabilizer selected from the group of MgO, CaO, CuO, ZnO, and CeO2. The method comprises sintering a shaped batch at 1600°-1800°C., quickly cooling the sintered shape to 1000°-1475°C., holding said shape within that temperature range to cause precipitation of tetragonal ZrO2 as islands within cubic ZrO2 grains, and then cooling to room temperature. The final product exhibits a microstructure consisting essentially of about 50-70% cubic ZrO2, greater than 20% and up to 50% tetragonal ZrO2, and less than 10% monoclinic ZrO2.

대표청구항 ▼

A ceramic body exhibiting a modulus of rupture in excess of 50,000 psi and a toughness greater than 5 MPag2 partially stabilized through the presence of 0.5-10% by weight Y2O3 as the primary stabilizing oxide and 1-10% by weight total of at least one secondary stabilizing oxide selected from the gro

A ceramic body exhibiting a modulus of rupture in excess of 50,000 psi and a toughness greater than 5 MPag2 partially stabilized through the presence of 0.5-10% by weight Y2O3 as the primary stabilizing oxide and 1-10% by weight total of at least one secondary stabilizing oxide selected from the group of MgO, CaO, CuO, ZnO, and CeO2, said body consisting essentially of about 50-70% by volume cubic ZrO2, greater than 20% and up to 50% by volume tetragonal ZrO2 present as islands within the cubic ZrO2 grains and having dimensions of about 0.25-0.75 micron, and less than 10% by volume monoclinic ZrO2 present along the grain boundaries and having dimensions of about 1-10 microns. A method for making a ceramic body exhibiting a modulus of rupture in excess of 50,000 psi and a toughness greater than 5 MPag2 partially stabilized through the presence of Y2O3 as the primary stabilizing oxide and at least one secondary stabilizing oxide selected from the group of MgO, CaO, CuO, ZnO, and CeO2 which comprises the steps of: (a) preparing a batch consisting essentially, in weight percent on the oxide basis, of 0.5-10% Y2O3, 1-10% total of at least one member of the group of MgO, CaO, CuO, ZnO, and CeO2, and the remainder ZrO2; (b) shaping said batch into a body of a predetermined configuration; (c) firing said body at a temperature between about 1600°-1800°C. for a period of time sufficient to produce an integral sintered body; (d) cooling said sintered body at a rate in excess of 100°C./hour to a temperature between about 1000°-1475°C.; (e) holding said body within that range of temperatures for a period of time sufficient to induce the precipitation of tetragonal ZrO2 as islands within cubic ZrO2 grains and having dimensions of about 0.25-0.75 microns, thereby producing a body consisting essentially of about 50-70% by volume cubic ZrO2, greater than 20% and up to 50% by volume tetragonal ZrO2, and less than 10% by volume monoclinic ZrO2 present along the grain boundaries and having dimensions of about 1-10 microns; and then (f) cooling said body to room temperature.