The effect of SiC whisker on the performances of Al2O3 matrixceramics mould for hollow turbine blade

Abstract

To improve the room-temperature and medium-temperature bending strengths of Al2O3 matrix ceramic mould for hollow turbine blade, SiC whisker was added. The samples' microstructure and phase were tested by Scanning Electron Microscope and X-Ray Diffraction, the relationship between the bending strength and phase were mainly analyzed. The result shows that the room-temperature bending strength of pre-sintering samples at 1250°C was respectively 19.6MPa and 54.75MPa when the content of SiC whisker was 4wt% and 8wt%. The medium-temperature bending strength of samples was respectively 1.56MPa to 0.91Mpa and 1.85MPa to 1.02MPa when the content of SiC whisker was 4wt% and 8wt% during 400°C to 600°C, and was the lowest at 500°C. After pre-sintering at 1250°C, the shrinkage of the samples with 4wt% and 8wt% SiC whisker was -0.06% and 0.7% respectively. It is possible to fabricate high-performance Al2O3 matrix ceramic mould for hollow turbine blade.