Sinterability and thermal properties of cordierite ceramics prepared from Algerian kaolinite and magnesium hydroxide

In this paper, we investigate the effect of MgO additions on the formation and densification behaviour of the cordierite obtained from some mixtures of Algerian kaolin and magnesium hydroxide. The sintering properties of these compositions have been evaluated by X-ray diffraction and bulk density. XRD analysis revealed that the major phase of the synthesized ceramics was cordierite along with a trace of spinel. Firing the pressed specimens at 1400 degrees C for 1 hour yielded a dense cordierite ceramics with a relative density higher than 96%, a negligible open porosity and a lower linear thermal expansion coefficient of 2.73x10(-6) K-1 between 200 and 800 degrees C. Cordierite due to its very low coefficient of thermal expansion is considered as promising candidate for advanced applications.