THERMAL-SHOCK PARAMETERS OF CERAMICS EVALUATED BY INFRARED RADIATION HEATING

An infrared radiation (IR) heating method was used to evaluate thermal shock parameters (thermal shock strength and thermal shock fracture t oughness) of float glass and alumina. This technique makes it possible to evaluate the parameters directly from the electric power of the IR heater. In this paper we discuss how the pertinent thermal shock para meters should be estimated both as physical properties of a material a nd as a function of temperature. The stress intensity factors for a di sk with an edge crack were analyzed numerically under a thermal shock loading. The thermal shock parameters in both ambient and elevated-tem perature environments were measured by the IR heating technique and th e results were compared with predicted values, which combined such tem perature-dependent properties of the material as Young's modulus, ther mal conductivity, linear thermal expansion, and tensile strength or fr acture toughness.