To improve the oxidation resistance of carbon/carbon （C/C） composites in air at high temperatures, a SiC- MoSi2/ZrO2-MoSi2 coating was prepared on the surface of C/C composites by pack cementation and slurry method....To improve the oxidation resistance of carbon/carbon （C/C） composites in air at high temperatures, a SiC- MoSi2/ZrO2-MoSi2 coating was prepared on the surface of C/C composites by pack cementation and slurry method. The microstructures and phase compositions of the coated C/C composites were analyzed by scanning electron microscopy and X-ray diffraction, respectively. The result shows that the SiC-MoSi2/ZrO2-MoSi2 coating is dense and crack-free with a thickness of 250-300 μm. The preparation and the high temperature oxidation property of the coated composites were investigated. The as-received coating has excellent oxidation protection ability and can protect C/C composites from oxidation for 260 h at 1773 K in air. The excellent anti-oxidation performance of the coating is considered to come from the formation of ZrSiO4, which improves the stability of the coating at high temperatures.展开更多
In order to improve the lifetime of continuous casting,ZrO_2-MoSi_2 composite powder used for plasmaspraying was prepared via spray drying and vacuum sintering.The microstructure and characteristics of the powder were...In order to improve the lifetime of continuous casting,ZrO_2-MoSi_2 composite powder used for plasmaspraying was prepared via spray drying and vacuum sintering.The microstructure and characteristics of the powder were investigated by particle size analysis,scanning electron microscopy and X-ray diffraction,respectively.The results show that the average viscosity and settlement rate are 60.43 mPas and 1.86%,respectively,when adding ammonium polyacrylate as a dispersant and polyvinyl alcohol as a binder.The powder obtained at the solid content of 70 wt.%,the dispersant amount of 1wt.%,the binder of 10 wt.%,and the sintering temperature of 1200 "C has the spherical agglomerate and a moderate size,which can be melted on the composite coating surface with a good compactness via plasma-spraying.展开更多
基金Projects(51221001,51222207)supported by the National Natural Science Foundation of ChinaProject(090677)supported by the Program for New Century Excellent Talents in University of ChinaProject(B08040)supported by Program of Introducing Talents of Discipline to Universities,China
文摘To improve the oxidation resistance of carbon/carbon （C/C） composites in air at high temperatures, a SiC- MoSi2/ZrO2-MoSi2 coating was prepared on the surface of C/C composites by pack cementation and slurry method. The microstructures and phase compositions of the coated C/C composites were analyzed by scanning electron microscopy and X-ray diffraction, respectively. The result shows that the SiC-MoSi2/ZrO2-MoSi2 coating is dense and crack-free with a thickness of 250-300 μm. The preparation and the high temperature oxidation property of the coated composites were investigated. The as-received coating has excellent oxidation protection ability and can protect C/C composites from oxidation for 260 h at 1773 K in air. The excellent anti-oxidation performance of the coating is considered to come from the formation of ZrSiO4, which improves the stability of the coating at high temperatures.
文摘In order to improve the lifetime of continuous casting,ZrO_2-MoSi_2 composite powder used for plasmaspraying was prepared via spray drying and vacuum sintering.The microstructure and characteristics of the powder were investigated by particle size analysis,scanning electron microscopy and X-ray diffraction,respectively.The results show that the average viscosity and settlement rate are 60.43 mPas and 1.86%,respectively,when adding ammonium polyacrylate as a dispersant and polyvinyl alcohol as a binder.The powder obtained at the solid content of 70 wt.%,the dispersant amount of 1wt.%,the binder of 10 wt.%,and the sintering temperature of 1200 "C has the spherical agglomerate and a moderate size,which can be melted on the composite coating surface with a good compactness via plasma-spraying.
