Inelastic strain concentration in directionally solidified materials

The application of Directionally Solidified (DS) materials in the construction of hot section parts (blades, vanes) of a gas turbine results in improvement in the engine performance and durability. Inelastic strain, an important parameter in low cycle fatigue (LCF) life prediction methodology, may be evaluated using simplified methods like Neuber's rule and Equivalent Strain Energy Density Hypothesis. The objectives of the present investigation are to examine the validity of these methods in case of DS materials and to demonstrate using numerical methods that the low cycle fatigue life of DS materials is superior to isotropic materials.