Temperature Dependent Elastic Constants of Directionally Solidified Superalloys

Abstract

Directionally solidified superalloys have been extensively used as turbine blade materials to improve creep-rupture and thermal fatigue performances. Turbine blades are subjected to fluctuant temperature changes. Precise knowledge of material behavior at various temperatures is essential in design and service life evaluation of turbine blades. In this study, coaxial model is extended to consider temperature dependent engineering elastic constants. Although no existing theory predicts the temperature dependence engineering elastic constants over large range of temperature, these constants could be estimated based upon very limited experimental data of direction solidification specimens and other temperature dependent materials data. Excellent agreement is observed between estimations and experimental data of 45 deg and 90 deg off directionally solidified direction specimens.