| Owning excellent mechanical properties from ambient to elevated temperature, nanocomposite ceramics are considered as promising materials with their application in cutting-tools, bearing and engine components, et al. Components with complex shape can be made of nanocomposite ceramic by taking advantages of its superplasticity, which is an important way in near-net shape forming. ZrO2 (3Y)-CaO-SiO2-TiO2 nanocomposite ceramic was studied under the route of"powders synthesis—composite sintering—performance testing". The microstructures and mechanical properties of ZrO2(3Y)-CaO-SiO2-TiO2 nanocomposite ceramic have been investigated systematically.ZrO2(3Y)-CaO-SiO2-TiO2 powders with excellent chemical homogeneity were synthesized by heating of ethanol-aqueous salt solutions combined co-precipitation method. The influences of sintering temperature on compositions, phase composition, particle size and sintering activity were studied. TEM, SEM, XRD, BET and other instruments were used to test the whole process and identify the powder's characteristic. Nano-scaled ZrO2(3Y)-CaO-SiO2-TiO2 powders with particle size of 1520nm,specific surface area of 69.15m2·g-1 can be obtained. The powders also showed uniform grain size, less agglomeration and good sintering activity.ZrO2(3Y)-CaO-SiO2-TiO2 ceramic composite was obtained by vacuum hot- pressing sintering. The microstructure and the mechanical properties of the ceramics under different sintering temperature were investigated. After hot-pressing sintering at 1300℃, the average grain size of the ceramic material is about 230nm, the relative density is up to 97.8% and the hardness is 1400.58kgf·mm-2.Superplastic compressive tests demonstrate that the material behaves good deformability in temperature range of 1400℃to 1450℃. During the compression tests, the material did not show any strain softening, which was quite different from the results obtained in the tensile tests of this kind of material.
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