PSI - Issue 2_B

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com cienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Struc ural Integrity 2 (2016) 2535–2542 Available online at www.sciencedirect.com Structural Integrity Procedia 00 (2016) 000–000 Available online at www.sciencedirect.com Structural Integrity Procedia 00 (2016) 000–000

www.elsevier.com/locate/procedia www.elsevier.com / locate / procedia www.elsevier.com / locate / procedia

XV Portuguese Conference on Fracture, PCF 2016, 10-12 February 2016, Paço de Arcos, Portugal Thermo-mechanical modeling of a high pressure turbine blade of an airplane gas turbine engine P. Brandão a , V. Infante b , A.M. Deus c * a Department of Mechanical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisboa, Portugal b IDMEC, Department of Mechanical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisboa, Portugal c CeFEMA, Department of Mechanical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisboa, Portugal Abstract 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 company, 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. 21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy Unit cell simulations and porous plasticity modelling for recrystallization textures in aluminium alloys L.E.B Dæhli a, ∗ , J. Faleskog b , T. Børvik a , O.S. Hopperstad a a Structural Impact Laboratory (SIMLab), Centre for Research-based Innovation (CRI), Department of Structural Engineering, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway b Department of Solid Mech nics, R yal Institute of Technology, SE-100 44 Stockholm, Sweden Abstract The well-known Gurson model has been heuristically extended to incorporate e ff ects 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. c 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. Keywords: Porous plasticity; Plastic anisotropy; Unit cell simulations; Barlat Yld2004-18p; Gurson model 1. Introduction Wrought metal alloys used for engineering applications often exhibit anisotropic behaviour under plastic deforma tions. Rolling and subsequent annealing of aluminium alloys induces plastic anisotropy in which the material axes align with the rolling, normal, and transverse directions. The resulting textures are mainly composed of cube and goss generic textures (Barlat and Richmond, 1987) in addition to some degree of random texture. Such aluminium alloys are frequently employed in structural applications, for instance in automotive and marine industries. Hence, predictive material models capable of accounting for the microstructural evolution is of great importance for structural integrity assessment and design. 21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy Unit cell simulations and porous plasticity modelling for recrystallization textures in aluminium alloys L.E.B Dæhli a, ∗ , J. Faleskog b , T. Børvik a , O.S. Hopperstad a a Structural Impact Laboratory (SIMLab), Centre for Res arch-based Innovation (CRI), Department of Structur l Engineering, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway b Department of Solid Mechanics, Royal Institute of Technology, SE-100 44 Stockholm, Sweden Abstract The well-known Gurson model has been heuristically extended to incorporate e ff ects 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. c 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. Keywords: Porous pl sticity; Plastic anisotropy; Unit cell si ulations; Barlat Yl 2004-18p; Gurson m del 1. Introduction Wrought metal alloys used for engineering applications often exhibit anisotropic behaviour under plastic deforma tions. Rolling and subsequent annealing of aluminium alloys induces plastic anisotropy in which the material axes align with the rolling, normal, and transverse directions. The resulting textures are mainly composed of cube and goss generic textures (Barlat and Richmond, 1987) in addition to some degree of random texture. Such aluminium alloys are frequently employed in structural applications, for instance in automotive and marine industries. Hence, predictive material models capable of accounting for the microstructural evolution is of great importance for structural integrity assessment and design. Copyright © 2016 The Auth rs. Published by Elsevier B.V. This is an open access article u der the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). P review under responsibility of the Scientific Committee of ECF21. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Keywords: High Pressure Turbine Blade; Creep; Finite Element Method; 3D Model; Simulation.

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt ∗ Corresponding author. Tel.: + 47 73594677 E-mail address: lars.e.dahli@ntnu.no ∗ Corresponding author. Tel.: + 47 73594677 E-mail address: lars.e.dahli@ntnu.no

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Copyright © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ). Peer review under responsibility of the Scientific Committee of ECF21. 10.1016/j.prostr.2016.06.317 2452-3216 c 2016 The Authors. Published by Elsevier B.V. Pe r-review under responsibility of the Scientific Committee of ECF21. 2452-3216 c 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21.