Practice of Application of Thermal Cycle Tests in Studying the Thermal Fatigue of Materials

Abstract

The methods of thermal cyclic tests used for determining the thermal fatigue resistance of materials are analyzed using thermal cyclic maps (TC maps). These methods are based on the construction of the dependence of life time N on plastic strain in a cycle ε_p. An analysis showed that the dependence of N on ε_p does not give complete information on the thermal fatigue of materials, since it is built without consideration of the peculiarities of developing deformation related to their physicomechanical properties during a thermal cycle of tests. This is observed, for example, in the studies of single-crystal turbine blade materials, in which many conflicting data are obtained according to the results of testing VKNA-1V and ZhC6F alloys.