The creep deformation behaviour of a high pressure (cooled) turbine blade section is modelled using the finite element method. Realistic estimates of the thermal and mechanical loading expected during service are employed; properties for the single crystal superalloy CMSX-4 are assumed. The constitutive model accounts for both a 2 < 110 > tertiary creep in the γ matrix and a < 211 > shearing of the γ ′ phase. The results indicate that the load in the web decreases during service due to creep

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... ormation, because of the primary creep effect. It is demonstrated that a variation in the blade orientation of 20 • away from [001] causes a variation in the creep strain at 20 × 10 6 s (about 5500 h) of about a factor of two. Off-axis orientations experience higher stresses in the web and correspondingly greater primary creep strains in the cooler web locations. Uncertainties in the locations of the cooling holes of up to 0.2 mm are predicted to increase the creep strain by a factor of around 15%.