| Summary: | <p>Currently, there is no creep model of single crystal material in the popular finite element software. That is why the Hill model as well as assumption of blade consideration as isotropic is widely used. Crystallographic model based approaches described in the technical literature are difficult to implement in every day calculations and they require a large amount of experimental data including those of indefinable under tests. Another problems with which structural analysts face are that it is impossible to describe a diversity of creep curves by a single equation and a set of experimental data is limited.</p><p>Despite the fact that there are numerous creep models and theories there is no current theory that correctly describes all varieties of creep curves in a wide range of stresses and temperatures, even for isotropic materials.</p><p>This paper discusses a novel approach of taking into account material properties anisotropy in combination with ANSYS finite element analysis software to predict the stress–strain state kinetics of single-crystal nickel-based turbine blades. The approach is based on using “equivalent direction” of stress state and has been implemented in ANSYS as a user creep routine.</p><p>Thus, using the proposed approach enables us to generalize the characteristics defined under uniaxial tensile tests of specimens with different crystallographic orientations on the complex stress in single crystal blade.</p><p>One of the main advantages of the developed creep model, in addition to the possible taking into account the anisotropy of the characteristics, are that it allows using a limited set of experimental data and their relatively easy processing. The model can be adapted to new data in case of obtaining characteristics in different crystallographic orientations. This approach can be easily reduced down to the level of isotropic materials.</p><p>Based on comparative calculations results of a single-crystal blade using the developed model with and without consideration of characteristics anisotropy a significant effect of this consideration was shown.</p>
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