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The Al2O3-ZrO2(3Y)-SiC composite ceramics used in solar thermal power were prepared by micrometric Al2O3,nano-ZrO2 and SiC powders under the condition of pressureless sintering.The bulk density and bending strength of samples with 10vol% nano-ZrO2 sintered at 1480℃ were 3.222 g/cm3 and 160.4MPa,respectively.The bending strength of samples after 7 times thermal shock tests (quenching from 1000℃ to 25℃ in air medium) is 132.0MPa,loss rate of bending strength is only 17%.The effect of nano-ZrO2 content on the microstructure and performance of Al2O3-ZrO2(3Y)-SiC composite ceramic was investigated.The experimental results show that the bending strength of samples with above 10vol% nano-ZrO2 content has decreased,because the volume expansion resulting from t-ZrO2 to m-ZrO2 phase transformation is excessive;Adding proper nano-ZrO2 would be contributed to improve the thermal shock resistance of the composite ceramics.The Al2O3-ZrO2(3Y)-SiC composite ceramic has promising potential application in solar thermal power.
The Al2O3-ZrO2 (3Y) -SiC composite ceramics used in solar thermal power were prepared by micrometric Al2O3, nano-ZrO2 and SiC powders under the condition of pressureless sintering. The bulk density and bending strength of samples with 10 vol% nano-ZrO2 sintered at 1480 ℃ were 3.222 g / cm3 and 160.4MPa, respectively.The bending strength of samples after 7 times thermal shock tests (quenching from 1000 ℃ to 25 ℃ in air medium) was 132.0MPa, loss rate of bending strength was only 17% The effect of nano-ZrO2 content on the microstructure and performance of Al2O3-ZrO2 (3Y) -SiC composite ceramic was investigated. The experimental results show that the bending strength of samples with above 10vol% nano-ZrO2 content has decreased because because the Volume expansion resulting from t-ZrO2 to m-ZrO2 phase transformation is excessive; Adding proper nano-ZrO2 would be contributed to improve the thermal shock resistance of the composite ceramics. Al2O3-ZrO2 (3Y) -SiC composite ceramic has promising potential applications ation in solar thermal power.