  The development of thermal stresses inside refractory ceramics experiencing
severe thermal shock is studied. The present analysis departs from the linear
theory of thermal stresses as it accounts for temperature dependent thermal and
mechanical material properties. Radiation surface heat exchange between the
refractory component and its surroundings is included. A Finite Element
Procedure is presented and a MATLAB code is developed. The nonlinear heat
equation is solved for the temperature field and this solution is subsequently
used in order to determine the stress field evolution. The finite element code
is validated and used for the thermal shock estimation of a refractory brick.
Material properties corresponding to Al 2O3 are selected. A thermal cycle
consisting of a heating stage followed by cooling down is simulated. The
results are compared with those predicted by the linear thermal stresses theory
and significant deviations are observed for the examined values of the Biot
number.
