PSI - Issue 2_A

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com ienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Struc ural Integrity 2 (2016) 3407–3414 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2016) 000–000 il l li t . i i t. t t l t it i

www.elsevier.com/locate/procedia . l i . /l t / i

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 Damage Evolution in Thermomechanical Loading of Stainless Steel R. Petráš a,b , V. Škorík b , J. Polák a,b* a CEITEC IPM, Institute of Physics of Material s ASCR, Žižkova 22, 616 62 Brno, Czech Republic b Institute of Physics of Materials ASCR , Žižkova 22, 616 62 Brno, Czech Republic Abstract Superaustenitic stainless steel Sanicro 25 has been subjected to in-phase and out-of-phase thermomechanical fatigue (TMF). Different amplitudes of mechanical strain and the changes of the temperature in the interval 250 to 700°C were applied to standard cylindrical specimens. Early fatigue damage has been studied using scanning electron microscopy combined with FIB cutting and EBSD imaging. TMF loading resulted first in developing thin oxide layer. In in-phase loading grain boundaries were preferentially oxidized and fatigue cracks developed by alternating oxidation and cracking. Fatigue cracks developed rapidly in oxidized grain boundaries and propagated intergranularly. During out-of-phase TMF loading the cracked oxide layer resulted in local oxidation and crack initiation. The crack grew transgranularly . © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. Keywords: Therm mechanical fatigue; Sanicro 25 steel; Damage mechanis ; FIB cutting; Localized oxidation-cracking 1. Introduction Electrical energy is currently the most widely used type of e ergy around the world. Coal has a dominant role in worldwide el ctricity gener ti n, Reddy (2013). Design and construction of novel, more efficient installations requires the usage of materials resisting severe loading and environmental conditions. Thermal and mechanical stresses in components during service produce variable strains and result in initiation and propagation of fatigue cracks. Low cycle fatigue, thermomechanical fatigue, creep-fatigue interaction, creep rupture strength under environmental conditions have to be considered in order to determine the rate of damage in materials working at elevated temperatures. , k b lák a,b* a , tit t f i f t i l , i , , li b tit t f i f t i l , i , , li Abstract t iti t i l t l i j t t i t t i l ti . i t lit des of mechanical strain and the changes of the temperature in the interval 250 to 700°C were applied to standard cylindrical specimens. Early fatigue damage has been studied u i i l t i i it tti i i . l i lt i t i l i t i i l . i l i i i ti ll i i ti l lt ti i ti i . ti l i l i i i i i t i t l l . i t l i t i l lt i l l i ti i iti ti . t l l t . li l i . . i i ilit t i ti i itt . i l ti ; i t l; i ; tti ; li i ti i . . e , . , . . , , , elevated temperatures. 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.: +420 532 290 366; E-mail address: polak@ipm.cz (J. Polák) i t . l.: ; il l i . . l

* 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. l i . . i i ilit t i ti i itt . t . li

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.2016.06.425