Effect of silica fiber on the mechanical and chemical behavior of alumina-based ceramic core material

In order to improve the chemical leachability, the alumina-based ceramic core material with the silica fiber was injected and sintered at 1100 degrees C/4 h, 1200 degrees C/4 h, 1300 degrees C/4 h and 1400 degrees C/4 h, respectively. The micrographs of ceramic core materials at sintered and leached state were characterized by scanning electron microscopy (SEM). The phase composition of ceramic core material after sintering and the leaching product after leaching were detected by X-ray diffraction (XRD). The porosity, room temperature bend strength, creep property at elevated temperature and the leaching rate in aqueous caustic solution were studied. The experimental results show that the ceramic core material with silica fiber obtain a fair balance between mechanical and chemical properties at sintering of 1300 degrees C/4 h. Specifically, the leach rate of ceramic core material with silica fiber is increased apparently. High leaching surface and weak adhesive strength between agglomerated alumina particles are the reasons that responsible for the ceramic core material with silica fiber be leaching fast than that of the ceramic core material without fiber. (C) 2017 The Ceramic Society of Japan and the Korean Ceramic Society. Production and hosting by Elsevier B. V. This is an open access article under the CC BY-NC-ND license.