SHAPED SINTERED CERAMIC BODIES COMPOSED OF Y2O3-STABILIZED ZIRCONIUM OXIDE AND PROCESS FOR PRODUCING A SHAPED SINTERED CERAMIC BODY COMPOSED OF Y2O3-STABILIZED ZIRCONIUM OXIDE

摘要

The invention relates to a shaped sintered ceramic body which contains Y2O3-stabilized zirconium oxide, has a sintered density of at least 99% of the theoretical sintered density and is characterized in that the shaped sintered body has an average grain size of < 180 nm and the zirconium oxide fraction of the shaped sintered body consists of tetragonal phase and cubic phase. The shaped sintered body is stable to hydrothermal ageing at 134°C and 2 bar in a water vapour atmosphere for at least 120 hours. The invention further relates to a process for producing a shaped sintered ceramic body containing a Y2O3-stabilized zirconium oxide, which comprises the steps: dispersing a submicron powder; comminuting the dispersed submicron powder, where the submicron powder having a diameter of equal to or less than 100 µm is comminuted by means of milling media to a particle size d95 < 0.42 µm; shaping the dispersion to form a body and sintering the body to give the shaped sintered body. The shaped sintered body of the invention can be used for implants, linings of industrial plants and for industrial components which can be subject to hydrothermal ageing.