PSI - Issue 2_B

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ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com Sci ceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Struc ural Integrity 2 (2016) 1652–1659 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 Modified Shape of Dynamic Master Curves due to Adiabatic Effects Thomas Reichert*, Wolfgang Böhme and Johannes Tlatlik Fraunhofer Institute for Mechanics of Materials IWM, Wöhlerstrasse 11, D-79108 Freiburg, Germany Abstract Within a joint project of IWM/Freiburg and MPA/Stuttgart the fracture toughness of a 22 NiMoCr 3 7 steel (A 508 Cl.2) was characterized at IWM with SE(B)10/10- und SE(B)40/20-specimens at -20 °C and high crack loading rates in the range of 10 3 to 10 6 MPa √ m s -1 , see Böhme et al. (2012 and 2013). The single temperature Master Curve evaluation according to ASTM E1921 and Wallin (2011) resulted in part in 5%-lower-bound fracture toughness versus temperature curves below the deterministic ASME lower bound K IR -reference-curve. At a first glance, this seems t violate the ASME K IR -concept, however, possibly this just indicates, that the conventional MC-evaluation has to be modified for elevated loading rates. Adiabatic heating in the vicinity of the crack tip could be one reason for that, as already argued in Schindler (2013 and 2015). Therefore, additional SE(B)-tests at temperatures of -20 °C, 0 °C and +20 °C were performed at IWM within the current follow up joint IWM-MPA project. The new IWM-results show in agreement with previous investigations by Viehrig et al. (2010) and Schindler et al. (2013 and 2015) that the Master Curves at elevated loading rates are steeper than at quasistatic loading, probably due to local adiabatic heating in the vicinity of the crack tip. Therefore, the temperature field around the crack tip has been measured with a high speed infrared camera and has been compared to results of a numerical simulation. Up to crack initiation, a local adiabatic rise in temperature of the order of magnitude of about 60 K was measured and calculated in the vicinity of the crack tip at a crack loading rate of about 10 6 MPa √ m s -1 . In order to take into account this adiabatic effect, the dynamic master curves were evaluated by applying an adjusted MC shape parameter. This finally leads to more plausible results for the dynamic Master Curves. Thus, the choice of a rate dependent shape parameter p should be considered for future modifications of the elevated loading rate appendix of ASTM E1921. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. 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: Fracture mechanics; high loading rates; dynamic Master Curve; K IR -curve

Keywords: High Pressure Turbine Blade; Creep; Finite Element Method; 3D Model; Simulation.

* Corresponding author. Tel.: +49-761-5142-390; fax: +49-761-5142-401 E-mail address: thomas.reichert@iwm.fraunhofer.de

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under 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 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.2016.06.209