Crystallographic life model for single crystal turbine blade and validation by the miniature specimens cut from the turbine blades

Purpose – The purpose of this paper is to found a life model for the single crystal (SC) turbine blade based on the rate‐dependent crystallographic plasticity theory.Design/methodology/approach – This life model has taken into consideration the creep and fatigue damages by the linear accumulation theory. A SC blade was taken from an aero‐engine, which had worked for 1,000 hours, as the illustration to validate the life model.Findings – The crystallographic life model has a good prediction to the life and damage of the SC turbine blade. In the mean time, the micro damage study of the miniature specimens showed that creep damage has more serious influence on the material performance in the blade body but it is fatigue damage in the blade rabbet.Originality/value – The life model can reflect the crystalline slip and deformation and crystallographic orientation of nickel‐based SC superalloys.

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