Thermal fatigue in structural components of flying vehicles engines

The paper deals with the problems of deformation and damage of the materials of structural components of complex shape subjected to cyclic loading by convective thermal flows which induces in them non-uniform temperature and thermal-stress fields. A new testing technique is proposed employing the use of models of different shape and, in particular, those of wedge-shape prism type. Variation of the level of thermal stresses and temperatures, as well as of the degree of non-uniformity of temperature and stress fields, is effected by changing the models dimensions under the given thermal loading conditions. It is shown that in simultaneous testing of a great number of models of different size it is possible to obtain information sufficient for deriving the equations of the material state under complex thermo-mechanical loading in aggressive gas flows. Examples are presented of practical application of the technique proposed.