Development of a high thermal shock resistant ceramic body suitable for cookware applications

Abstract

Development of a ceramic based cookware body with adequate thermal shock resistance was successfully developed using low cost raw materials. The objective of this work was to develop a ceramic body composition suitable for cookware to be used in direct flame cooking. To achieve this objective, cookware body should have low thermal expansion coefficient, high strength, low water absorption and high thermal shock resistance. In this study, ball clay, talc, alumina and zirconium silicate were used as starting raw materials and twenty five samples were investigated with different compositions. All samples were wet-mixed, shaped by slip casting, dried and fired to a temperature of 1250°C in an electric furnace. Modulus of Rupture was tested by the three point bending method, the thermal conductivity of each body was measured with Lee's disk method and the coefficient of thermal expansion was measured by thermo mechanical analyzer. The thermal shock resistance of each sample was calculated with Kingery's formula. Optimum thermal shock resistance of 0.74 kJm-VHvas achieved for a body composition of 45% of clay, 15% of talc, 15% of alumina and 25% of zirconium silicate which was fired to 1250°C. Further, modulus of rupture and coefficient of thermal expansion of the ceramic body were 74 MPa and 30.2*10-7 K-1, respectively. These results suggest that the ceramic body is suitable to be used in cookware applications.