Abstract: The analytical formulae of one-dimensional unsteady temperature field and unsteady thermal stress field for a functionally gradient material plate with symmetrical structure are derived by using perturbation method, by which the unsteady temperature fields and unsteady thermal stress fields of an AL2O3/(W, Ti)C functionally gradient ceramic plate with symmetrical structure are calculated in the case of both surface cooling and surface heating. The method of improving the thermal shock resistance of ceramic tool materials i. e. using functionally gradient ceramic tool materials, is discussed and verified by intermittent turning tests.

Key words: Compositional distribution, Functionally gradient materials, Thermal shock resistance, Unsteady heat transfer, Unsteady thermal tress