SiC composite ceramics for solar absorber and storage integration are new concentrating solar power materials.SiC composite ceramics for solar absorber and storage integration were fabricated using SiC,black corundum ...SiC composite ceramics for solar absorber and storage integration are new concentrating solar power materials.SiC composite ceramics for solar absorber and storage integration were fabricated using SiC,black corundum and kaolin as the raw materials,Co_(2)O_(3)as the additive via pressureless graphite-buried sintering method in this study.Influences of Co_(2)O_(3)on the microstructure and properties of SiC composite ceramics for solar absorber and storage integration were studied.The results indicate that sample D2(5wt%Co_(2)O_(3))sintered at 1480℃exhibits optimal performances for 119.91 MPa bending strength,93%solar absorption,981.5 kJ/kg(25-800℃)thermal storage density.The weight gain ratio is 12.58 mg/cm2after 100 h oxidation at 1000℃.The Co_(2)O_(3)can decrease the liquid phase formation temperature and reduce the viscosity of liquid phase during sintering.The liquid with low viscosity not only promotes the elimination of pores to achieve densification,but also increases bending strength,solar absorption,thermal storage density and oxidation resistance.A dense SiO_(2) layer was formed on the surface of SiC after 100 h oxidation at 1000℃,which protects the sample from further oxidation.However,excessive Co_(2)O_(3)will make the microstructure loose,which is disadvantageous to the performances of samples.展开更多
We used different SiC particle size as raw materials and via reaction bonding technique to prepare porous SiC membrane supports.The phase composition,microstructure,bending strength,open porosity,and pore size distrib...We used different SiC particle size as raw materials and via reaction bonding technique to prepare porous SiC membrane supports.The phase composition,microstructure,bending strength,open porosity,and pore size distribution were investigated as a function of SiC particle size and firing temperature.It is found that the reduction of SiC particle size not only dramatically enhances the bending strength of porous SiC membrane supports,but also slightly reduces the firing temperature duo to smaller SiC particle with higher specific surface area and higher reaction activity.Besides,the open porosity and pore size distribution are dependent on the firing temperature,but insensitive to the SiC particle size due to the pore related characters mainly controlled by the binder.The bending strength increases with the increasing of the firing temperature and with the decreasing of SiC particle size.When the firing temperature was 1500℃and SiC average particle size was 447.75μm,the optimal performance were achieved,the bending strength was 15.18 MPa,the open porosity was 36.02%,the pore size distributed at 3.09-112.47μm,and the mean pore size was 14.16μm.展开更多
基金Funded by the National Key R&D Program of China(No.2018YFB1501002)。
文摘SiC composite ceramics for solar absorber and storage integration are new concentrating solar power materials.SiC composite ceramics for solar absorber and storage integration were fabricated using SiC,black corundum and kaolin as the raw materials,Co_(2)O_(3)as the additive via pressureless graphite-buried sintering method in this study.Influences of Co_(2)O_(3)on the microstructure and properties of SiC composite ceramics for solar absorber and storage integration were studied.The results indicate that sample D2(5wt%Co_(2)O_(3))sintered at 1480℃exhibits optimal performances for 119.91 MPa bending strength,93%solar absorption,981.5 kJ/kg(25-800℃)thermal storage density.The weight gain ratio is 12.58 mg/cm2after 100 h oxidation at 1000℃.The Co_(2)O_(3)can decrease the liquid phase formation temperature and reduce the viscosity of liquid phase during sintering.The liquid with low viscosity not only promotes the elimination of pores to achieve densification,but also increases bending strength,solar absorption,thermal storage density and oxidation resistance.A dense SiO_(2) layer was formed on the surface of SiC after 100 h oxidation at 1000℃,which protects the sample from further oxidation.However,excessive Co_(2)O_(3)will make the microstructure loose,which is disadvantageous to the performances of samples.
基金Funded by Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory(No.XHD2020-001)
文摘We used different SiC particle size as raw materials and via reaction bonding technique to prepare porous SiC membrane supports.The phase composition,microstructure,bending strength,open porosity,and pore size distribution were investigated as a function of SiC particle size and firing temperature.It is found that the reduction of SiC particle size not only dramatically enhances the bending strength of porous SiC membrane supports,but also slightly reduces the firing temperature duo to smaller SiC particle with higher specific surface area and higher reaction activity.Besides,the open porosity and pore size distribution are dependent on the firing temperature,but insensitive to the SiC particle size due to the pore related characters mainly controlled by the binder.The bending strength increases with the increasing of the firing temperature and with the decreasing of SiC particle size.When the firing temperature was 1500℃and SiC average particle size was 447.75μm,the optimal performance were achieved,the bending strength was 15.18 MPa,the open porosity was 36.02%,the pore size distributed at 3.09-112.47μm,and the mean pore size was 14.16μm.
