METHOD FOR REDUCING THERMAL EXPANSION OF CORDIERITE

摘要

PURPOSE: To provide a method for reducing a coefficient of thermal expansion of an anisotropic polycrystalline sintered ceramic product. CONSTITUTION: A coefficient of thermal expansion of an anisotropic polycrystalline sintered ceramic product is reduced during contacting by at least 1×10<-7> deg.C<-1> measured between 25 and 800 deg.C by bringing the ceramic product containing a cordierite as a main crystal phase, and an oxide composition containing 9 to 20 wt.% of MgO, 30 to 50 wt.% of Al2 O3 and 41 to 56.5 wt.% of SiO2 into contact with water either in a liquid or gaseous state.