Patent ID: 7722246

Claim:
A method of determining the coefficient of thermal expansion of a glaze or a refractory body, comprising: a) applying a glaze to the refractory body, wherein the refractory body is a substantially densified refractory body, wherein the glaze is characterized by a known elastic modulus, wherein the glaze is characterized by a known failure stress, wherein the glaze is characterized by a known glass transition temperature, and wherein the coefficient of thermal expansion of one of the glaze or the refractory body is known and the coefficient of the other of the glaze or the refractory body is unknown; b) bonding the glaze to the refractory body; c) putting the glaze into sufficient tension to induce crazing and to create cracks; d) measuring the average distance between cracks in the crazed glaze; and e) determining the unknown coefficient of thermal expansion of the glaze or refractory body according to the relationship wherein the difference between the known and unknown coefficients of thermal expansion is proportional to the failure stress of the glaze divided by the product of the elastic modulus of the glaze, the distance between the cracks in the crazed glaze, and the difference between the glass transition temperature of the glaze and the ambient temperature.