Search

In this study, alumina–zirconia ceramics with ZrO2components obtained using different methods were investigated. Synthesized undoped ZrO2powder, commercial powder of ZrO2, doped with 3 mol% Y2O3and commercial powder of monocline zirconia doped with 2 mol% ceria were used. Highly dispersed (D50 < 100 nm) undoped zirconia was synthesized by precipitation from 1 M aqueous solution of ZrOCl2-8H2O with 25% aqueous ammonia solution. The resultant products were treated with water and isopropyl alcohol. Thermal treatment of the powder was carried out in a chamber furnace at a temperature beginning at 450 °C. Increasing the content of undoped ZrO2synthesized using the precipitation method increased the average size of ZrO2grains from 370 ± 20 nm to 560 ± 25 nm. During sintering of alumina-zirconia ceramics containing 20 vol% highly dispersed undoped zirconia, clusters of ZrO2particles unite to form large grains (800–1100 nm). Zirconia crystals with sizes less than 300 nm in the ceramic structure are observed inside and in the joints of Al2O3grains. With the increase in total undoped zirconia content from 10 to 20 vol% in alumina–zirconia ceramics, the proportion of t-ZrO2remaining during sintering decreases from 6 to 2 vol%. The introduction of cerium nitrate into a suspension of monoclinic zirconia at the stage of dispersion leads to the formation of ceramic CeAl11O18platelets with length of up to ~ 2 μm and width of ~ 0.15 μm. The bending strength is 800 ± 50 MPa and fracture toughness is 5.4 ± 0.7 MPa*m1/2in Al2O3–ZrO2ceramics containing 15 vol% zirconia doped with 2 mol% ceria.