PSI - Issue 2_B

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com ScienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Struc ural Integrity 2 (2016) 1837–1844 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Available online at www.sciencedirect.com ScienceDirect 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 Strain En rgy Density Bas d Assessment of Cracked Terfenol-D Specimens Under Magnetic Field and Different Loading Rates Marco Colussi a , Filippo Berto a, *, Kotaro Mori b , Fumio Narita c a University of Padua, Department of Management and Engineering, Stradella S. Nicola 3, Vicenza 36100, Italy b Ibaraki University, Department of Mechanical Engineering, Nakanarusawa-cho 4-12-1, Hitachi 316-8511, Japan c Tohoku University, Department of Material Processing, Aoba-yama 6-6-02, Sendai 980-8579, Japan Abstract The purpose of this work is the characterization of the fracture behaviour of giant magnetostrictive materials subjected to a magnetic field. Both experimental and numerical investigations have been performed, focusing on iron and rare earth alloys, such as the commercially named Terfenol-D. Tests have been carried out on single-edge precracked specimens subjected to three point bending in the presence and absence of a magnetic field and fracture loads have been measured at different loading rates. Recent studies on local stress fields in proximity of crack and notch tips have shown that Strain Energy Density (SED), averaged in a circular control volume which includes a crack tip, could be a robust parameter in the assessment of brittle fracture resistance of several materials. Coupled-field analyses have then been performed on both plane stress and plane strain finite element models and the effect of the magnetic field on fracture resistance of Terfenol-D alloy was predicted in terms of averaged SED. A relationship between the SED's control volume size and the loading rate has also been proposed. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. Keywords: strain energy density; strain energy release rate; smart materials; giant magnetostrictive materials; fracture toughness; magnetic field. 21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy Strain Energy Density Based Assessment of Cracked Terfenol-D Specimens Under Magnetic Field and Different Loading Rates Marco Colussi a , Filippo Berto a, *, Kotaro Mori b , Fumio Narita c a University of Padua, Department of Management nd Engineering, Stradella S. Nicola 3, Vicenza 36100, Italy b Ibaraki University, Department of Mechanic l Engineering, Nakanarusawa-cho 4-12-1, Hit chi 316-8511, Japan c Tohoku University, Department of Material Processing, Ao a-yama 6-6-02, Sendai 980-8579, Japan Abstract The purpose of this work is the characterization of the fracture behaviour of giant magnetostrictive materials subjected to a magnetic fi ld. Both experimental and numerical investigations have been perf rmed, focusing on iron and ra e earth alloys, such as the commercially named Terfenol-D. T sts have been carried out o single-edge precracked specimens subjected to three point bending in the pres nce and absence of a magnetic field and fracture loads have b en m asured at different loa ing rat s. Recent studies on local stress fiel s in proximity of crack and notch tips have shown that Strain Ene gy Density (SED), ave g d in a circular control vo um which includes a crack tip, could be a robu t parameter in the assessment of brittle fracture resist nce of severa materials. Co pl d-field analys s have then been performed on both plane stress and plane strain finite element models and the effect of the magnetic field on fracture r sistance o Terfen l-D alloy was predicted in te ms of averaged SED. A relationship between the SED's control volume size and the loading ate has also been proposed. © 2016 The Authors. Published by Else ier B.V. Peer-review under respons bility of the Scientific Committee of ECF21. Keywords: strain energy density; strain energy release rate; smart materials; giant magnetostrictive materials; fracture toughness; magnetic field. 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/ icenses/by-nc-nd/4.0/). Peer-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. 1. Introduction Magnetostrictive materials exhibit deformation in resp nse to external magnetic fields and magnetization changes in response to applied forces. Among giant magn tostrictive materials, the commercially k own Terfenol-D (Tb 0.3 Dy 0.7 Fe 1.9 ) lloy, made out of iro , terbium and dysprosium, has been recording much nterest ver the y ars. Keywords: High Pressure Turbine Blade; Creep; Finite Element Method; 3D Model; Simulation. Magnetostrictive materials exhibit deformation in response to external magnetic fields and magnetization changes in response to applied forces. Among giant magnetostrictive materials, the commercially known Terfenol-D (Tb 0.3 Dy 0.7 Fe 1.9 ) alloy, made out of iron, terbium and dysprosium, has been recording much interest over the years. 1. Introduction

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review un er responsibility of the Scientific Committee of ECF21. 2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer review under r sponsibility of the Scientific Committee of ECF21. * Corresponding author. Tel.: +39 0444 998711; fax: +39 0444 998888. E-mail address: berto@gest.unipd.it * Corresponding author. Tel.: +39 0444 998711; fax: +39 0444 998888. E-mail ad ress: berto@gest.unipd.it

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.2016.06.231