PSI - Issue 3

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 Structu al Integrity 3 (2017) 484–497 Available online at www.sciencedirect.com Sci nceDir ct Structural Integrity Procedia 00 (2017) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2017) 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. XXIV Italian Group of Fracture Conference, 1-3 March 2017, Urbino, Italy Creep behaviou of 15-15Ti(Si) austenitic steel in air nd in liquid lead at 550°C A. Strafell ∗ , A. Coglito e, E. Salern tano ENEA- Italian National Agency for New Technologies, Energy and Sustainable Economic Development-Laboratory of Materials Technologies Faenza, Via Ravegnana, 186 - 48018 - Faenza, Italy This work aims at studying the creep behaviour of 15-15Ti(Si) austenitic steel, under uniaxial stress and its interaction with liquid lead. Creep tests were performed at 550 °C in an engineering stress range of 300-560 MPa. The 15-15Ti(Si) stainless steel is one of the best candidates for the nuclear reactor components of IV generation Lead-cooled fast reactor (LFR) and was tested in air and in stagnant liquid lead to simulate its behaviour in operating thermal and mechanical stress conditions and to verify its sensitivity to Liquid Metal Embrittlement (LME). Only few data can be found in the literature on 15-15Ti(Si) characterization, therefore the performed tests provided important information to use this material i the uclear field, allowing to obtain the characteristic curve simulating the creep behaviour in air at all s ress val es, ba d on the Norton law and experimental data. The results of the specimens in air were compared with those ob ain d in lead, providing important information on cre p corr sion: the liquid metal embrittlement effect takes place in lead and it produces decrease of eep-ruptur time, reduction of creep strain and then the loss f steel ductility. Moreover, Sc nning Electron Microscope (SEM) micrographs highlighted that lead changes both the mode and the type of specimen fracture. In addition, it was analyzed the lead action time, as the time after which the corrosion appears with macroscopic effects. These tests are still in progress: up to the current value of time (800h), they showed similar creep behaviour of the specimens tested in air and in lead. It can be assumed that liquid etal embrittlement takes place after a long time of steel/lead contact. However, since these tests are ongoing, these results will be object of our future studies. © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of IGF Ex-Co. XXIV Italian Group of Fracture Conference, 1-3 March 2017, Urbino, Italy Creep behaviour of 15-15Ti(Si) austenitic steel in air and in liquid lead at 550°C A. Strafella ∗ , A. Coglitore, E. Salernitano ENEA- Italian National Agency for New Technologies, Energy and Sustainable Economic Development-Laboratory of Materials Technologies Faenza, Via Ravegnana, 186 - 48018 - Faenza, Italy Abstract This work aims at studying the creep behaviour of 15-15Ti(Si) austenitic steel, under uniaxial stress and its interaction with liquid lead. Creep tests were performed at 550 °C in an engineering stress range of 300-560 MP . Th 15-15Ti(Si) stainless steel is one of the b st candidates fo the nuclear reactor components of IV generation Lead cooled f st reactor (LFR) and wa tested n air and in stagnant l quid lead to simulate its behaviour i operating therm l a d mechanical stress conditions and to verify its sensitivity to Liquid Metal Embrittle ent (LME). Only few data ca be found i the literature on 15-15Ti(Si) characterization, therefore the performed tests provided important information o use this material in the n clear field, allowing to obtain the c aracteristic cu ve simulating the cr ep behaviour i air at all s ress values, based on the Norton law and exper mental data. T results of the specimens in air w re compared with those obtained in lead, provi ing important information on creep corrosion: the liqui m tal embrittlement eff ct takes place i lead a d it produc s a decrease of creep-rupture time, a reduction of cre p strain and then the loss of steel ductility. Moreover, S anning Electr n Microscope (SEM) micrographs highligh d that l d ch nges both the mode and h typ of specimen f acture. I addition, it was a alyzed the ad action time, as th time after which the c rosion appears w th macro cop c effects. These tests are still in progress: up t the current v lue of tim (800h), they showed simil r creep behaviour of the sp cim ns t sted in air and in lead. It can be ssumed that liquid metal embrittlement akes place after a long time of steel/lead contact. However, si ce these tests are ongoing, these results will be object of our future studies. © 2017 The Authors. Published by Elsevier B.V. Peer-review under espons bility of the Scientific Committee of IGF Ex-Co. Keywords: 15-15Ti(Si); austenitic stainless steel creep; creep curves; steady strain creep rate; Liquid Metal Embrittlement (LME); creep tests in lead © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Copyright © 2017 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativ commons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the Scientific Committee of IGF Ex-Co. Keywords: 15-15Ti(Si); austenitic stainless steel creep; creep curves; steady strain creep rate; Liquid Metal Embrittlement (LME); creep tests in lead Keywords: High Pressure Turbine Blade; Creep; Finite Element Method; 3D Model; Simulation. Abstract

∗ Corresponding author. E-mail address: alessandra.strafella@enea.it ∗ Corresponding author. E-mail address: alessandra.strafella@enea.it

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452-3216 © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of IGF Ex-Co. 2452-3216 © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of IGF Ex-Co.

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Copyright © 2017 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 IGF Ex-Co. 10.1016/j.prostr.2017.04.061