Formation of dumbbell-shaped β-SiC whiskers in Al2O3-ZrO2-C composite refractories

摘要: Based on thetraditional processing route of carbon-bonded materials, alumina powder, silicon graphite flakes, carbon black as well phenolic resin are mixed, pressed to samples and fired in a coke bed at between 1200 °C 1600 °C. Their phase composition microstructure determined observed with the aid XRD, SEM, EDX TEM. The evolution function temperature influences bulk density, apparent porosity mechanical strength. formation SiC whiskers cristobalite balls temperatures 1300 influence primarily properties. amount increases temperature. However, morphology produced different is remarkably diverse. In range 1400 °C, most β-SiC nano-sized diameter micrometer-sized length, some them dumbbell-shaped distributed matrix. At above 1500 become curled, coarser congregated. structure loosened due escape great gaseous and/or monoxide. can be situ functional components such nozzles or slide gate systems prefabricated incorporated fine material bonded recipes for advanced composite materials system Al 2 O 3 -ZrO -C superior thermo-