Effect of Sintering Temperature on Ceramic Cores Performances of SiO_2-ZrO_2 system

The easy leachable SiO2-ZrO2 ceramic cores used in directional solidification and single crystal hollow blades were prepared by traditional hot-pressure casting.The results show that the a sintering shrinkage increased with the increasing sintering temperature from 1150℃ to 1250℃,and sintering shrinkage is increased markedly above 1200℃.Well-grown crystalline grains were shown,and main compositions are composed with non-crystal silica,cristobalite and zirconia.The material properties sintering at 1200℃ are optimized,and bending strengths reach 42.9MPa,and best anti-deformation and bending strengths are also obtained at 1550℃.High temperature anti-deformation is 0.1mm,and the high temperature bending strength,pore,densiy and sintering shrinkage are 27.9MPa,30.4%,1.92g/cm3 and 0.4% respectively.The formations of cristobalite is about 20%.It meets the pouring requirement for superallay hollow turbine blades of the aero-engine.