Preparation of cordierite/ZrO₂ nano-composite powders by a colloidal coating process

Cordierite/ZrO₂ nano-composite powders were prepared by a colloidal coating process. Cordierite particles are embedded within a continuous layer of fine amorphous ZrO₂ that was provided by the colloidal processing after drying. Tetragonal ZrO₂ was first formed at 650°C and monoclinic ZrO₂ phase was identified at the calcination temperature of 800°C. After calcination at 850°C, crystallized ZrO ₂ particles with the size from 10 nm to 30 nm homogeneously covered the surface of cordierite particles. Cordierite/ZrO₂ nano-composite powders prepared by a colloidal coating process show better sinterability than that of cordierite/ZrO₂ powder mixtures prepared by a conventional mixing method, and were sintered to a density of over 96% at a low temperature of 1300°C.