PSI - Issue 2_A

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) 2989–2993 Available online at www.sciencedirect.com Sci nceD rect Structural Integrity Procedia 00 (2016) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2016) 000–000

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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 Effect of pulsed el ctric c rrent on the growth behavior of fatigue crack in Al alloy Jaewoong Jung a , Yang Ju b *, Yasuyuki Morita b , Yuki Toku b a Graduate student, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan b Faculty of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan Abstract The growth of fatigue crack in aluminum alloy, 6061-T6, under the application of pulsed electric current was studied. To examine the effect of pulsed electric current, different electric current densities were used at different fatigue cycles, where the electric current densities were subjected as 90 A/mm 2 and 150 A/mm 2 . With the electric current density of 90 A/mm 2 , the fatigue life was increased. However, when the current density levels became higher, that is, 150 A/mm 2 , the fatigue life was decreased. From the fracture surface observations, the local melting was found on crack surface. It is concluded that the increase of fatigue life is attributed to the crack shi lding effect resulted from the local melting induced by the pulsed electric curren . In addit on, th effect of pulsed electric current was more remarkable in small crack region. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. Keywords: Fatigue; Pulsed electric current, Aluminum alloy, crack propagation 1. Introduction There are many tudies to improve the long term duration and reliability of machine parts under cyclic loads. Esp cially, the effect of pulsed electri current has be n found to be able to improve the fatigue properties and the mechanical properties of materials. Karpenko et al. (1976) showed that the low cycle fatigue life of steel was prolonged by the application of pulsed electric current. Conrad et al. (1991) demonstrated that the fatigue life of copper was increased by the effect of the pulsed electric current. They concluded that the electric current influenced 21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy Effect of pulsed electric current on the growth behavior of fatigue crack in Al alloy Jaewoong Jung a , Yang Ju b *, Yasuyuki Morita b , Yuki Toku b a Graduate student, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan b Faculty of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan Abstract The growth of fatigue crack in aluminum alloy, 6061-T6, under the application of pulsed electric current was studied. To examine the effect of pulsed electric current, different electric current densities were used at diff rent fatigue cycles, wh re the electric current densities w re subje ted as 90 A/mm 2 and 150 A/mm 2 . With the el ctric current density of 90 A/mm 2 , the fatigu lif was increased. Howev , when th current density levels beca e higher, that is, 150 A/mm 2 , the fatigue life was decreased. From the fracture surfac observations, the local melting wa found on crack surface. It is concluded that the incre se of fatigue life is attributed to the rack shieldi g eff ct result d from the local melting induced by the pu sed electric current. In addition, th effect of pulsed el ct ic current was more r markable in sma l rack region. © 2016 The Aut ors. Publish d by Elsevier B.V. Peer-review under espons bility of the Scientific Committee of ECF21. Keywords: Fatigue; P lsed electric current, Aluminum alloy, crack propagation 1. Introduction There are many studies to improve the long term duration and reliability of machine parts under cyclic loads. Especially, the effect of pulsed electric current has been fou d to be able to improve th fatigue properties and the mechanical prop ti s of ma erials. Karpenko et al. (1976) sh w d that the low cycl fatigue life of teel was prolonged by the application of pulsed el ctric current. Conrad et al. (1991) demonstrated that the fatigu life of copper was incr ased by he effect of the pulsed electric current. They concluded that the lectric curren influenced 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. © 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 2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review und r responsibility of the Scientific Committee of ECF21. 2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. * Corresponding author. Tel.: +81-52-789-4672; fax: +81-52-789-3109. E-mail address: ju@mech.nagoya-u.ac.jp * Corresponding author. Tel.: +81-52-789-4672; fax: +81-52-789-3109. E-mail address: ju@mech.nagoya-u.ac.jp

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.2016.06.374