摘要 |
A ceramic article which consists essentially, by weight on the oxide basis, of 10-25% SiO2, 65-85% Al2O3, and 2-12% Li2O and comprises beta-eucryptite as a first phase having a negative component in thermal expansion and a melting point Tm1, and a second phase having a positive component in thermal expansion which is higher than the component in thermal expansion of the first phase and a melting point Tm2, wherein Tm2>Tm1, wherein the first phase is at most 50% by weight of the ceramic, and wherein the ceramic is characterized by microcracking. Tm2 is at least 1800° C. The ceramic article exhibits a near zero coefficient of thermal expansion from room temperature to 800° C., a high refractoriness, and a high resistance to thermal shock properties which make the inventive ceramic extremely desirable in high temperature applications, such as filters for diesel exhaust engines.
|