During their operation, modern aircraft engine components are subjected to increasingly demanding operating conditions, especially the high pressure turbine (HPT) blades. Such conditions cause these parts to undergo different types of time-dependent degradation, one of which is creep. A model using the finite element method (FEM) was developed, in order to be able to predict the creep behaviour of HPT blades. Flight data records (FDR) for a specific aircraft, provided by a commercial aviation

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... mpany, were used to obtain thermal and mechanical data for three different flight cycles. In order to create the 3D model needed for the FEM analysis, a HPT blade scrap was scanned, and its chemical composition and material properties were obtained. The data that was gathered was fed into the FEM model and different simulations were run, first with a simplified 3D rectangular block shape, in order to better establish the model, and then with the real 3D mesh obtained from the blade scrap. The overall expected behaviour in terms of displacement was observed, in particular at the trailing edge of the blade. Therefore such a model can be useful in the goal of predicting turbine blade life, given a set of FDR data. Abstract The well-known Gurson model has been heuristically extended to incorporate effects of matrix anisotropy on the macroscopic yielding of porous ductile solids. Typical components of recrystallization textures for aluminium alloys were used to calibrate the Barlat Yld2004-18p yield criterion using a full-constraint Taylor homogenization method. The resulting yield surfaces were further employed in unit cell simulations using the finite element method. Unit cell calculations are invoked to investigate the evolution of the approximated microstructure under pre-defined loading conditions and to calibrate the proposed porous plasticity model. Numerical results obtained from the unit cell analyses demonstrate that anisotropic plastic yielding has great impact on the mechanical response of the approximated microstructure. Despite the simplifying assumptions that underlie the proposed constitutive model, it seems to capture the overall macroscopic response of the unit cell. However, to further enhance the numerical predictions, the model should be supplemented with a void evolution expression that accounts for directional dependency, and a void coalescence criterion in order to capture the last stages of deformation. Abstract The well-known Gurson model has been heuristically extended to incorporate effects of matrix anisotropy on the macroscopic yielding of porous ductile solids. Typical components of recrystallization textures for aluminium alloys were used to calibrate the Barlat Yld2004-18p yield criterion using a full-constraint Taylor homogenization method. The resulting yield surfaces were further employed in unit cell simulations using the finite element method. Unit cell calculations are invoked to investigate the evolution of the approximated microstructure under pre-defined loading conditions and to calibrate the proposed porous plasticity model. Numerical results obtained from the unit cell analyses demonstrate that anisotropic plastic yielding has great impact on the mechanical response of the approximated microstructure. Despite the simplifying assumptions that underlie the proposed constitutive model, it seems to capture the overall macroscopic response of the unit cell. However, to further enhance the numerical predictions, the model should be supplemented with a void evolution expression that accounts for directional dependency, and a void coalescence criterion in order to capture the last stages of deformation.