PSI - Issue 13

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at www.sciencedire t.com ienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structural Integrity 13 (2018) 1099–11 4 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural I tegrity Procedia 00 (2018) 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. ECF22 - Loading and Environmental effects on Structural Integrity Atomistic modelling of light-element co-segregation at structural defects in iron Eunan J. McEniry 0F0F *, Tilmann Hickel and Jörg Neugebauer Department of Computational M aterials Design, Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Straße 1, 40237 Düsseldorf, Germany Abstract Studying the behaviour of hydrogen in the vicinity of extended defects, such as grain boundaries, dislocations, nanovoids and phase boundaries, is critical in understanding the phenomenon of hydrogen embrittlement. A key complication in this context is the interplay betwe n hydrogen and other se regating elements. Modelling the competition of H with other light elements requires an efficient description of the interactions of compositionally complex systems, with the system sizes needed to appropriately describe extended defects often precluding the use of direct ab initio approaches. In this regard, we have developed novel electronic structure approaches to understand the energetics and mutual interactions of light elements at representative structural features in high-strength ferritic steels. Using this approach, we examine the co-segregat ion of hydrogen with carbon at chosen grain boundaries in α -iron. We find that the strain introduced by segregated carbon atoms at tilt grain boundaries increases the solubility of hydrogen close to the boundary plane, giving a higher H concentration in the vicinity of the boundary than in a carbon-free case. Via simulated tensile tests, we find that the simultaneous presence of carbon and hydrogen at grain boundaries leads to a significant decrease in the elongation to fracture compared with the carbon-free case. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: cosegregration, simulation & modelling, grain boundary fracture © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. ECF22 - Loading and Environmental effects on Structural Integrity Atomistic modelling of light-element co-segregation at structural d fects in iron Eunan J. McEniry 0F0F *, Tilmann Hickel and Jörg Neugebauer Department of Computational M aterials Design, Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Straße 1, 40237 Düsseldorf, Germany Abstract Studying the behaviour of hydrogen in the vicinity of extended defects, such as grain boundaries, dislocations, nanovoids and phase boundaries, is critical in understandi g the phenomenon of hydrogen embrittlement. A key compli ti i this context is th interpl y between hydrogen and other segr gating eleme ts. Mo elling the competition of H with other light elements requires an efficient description of the int ract ons of compositionally complex systems, with the syst m sizes needed t appropriately describe xtended defects ften precluding the use of direct ab initio approaches. In this regard, we have develope n vel electronic stru tur approaches to understand the energetics and mutual interactions of light elements at representative structural features in high-strength ferritic st els. Using this approach, we exa ine the co-segregat ion of hydrogen with carbon at chosen grain boundaries in α -iron. We find that the strain introduced by segregated carbon atoms at tilt grain boundaries increases the solubility of hydrogen close to the boundary plane, givi g a high r H conc ntration in the vicinity of the boundary tha in a carbon-free case. Via simulated tensil tests, we find that the simultaneous presence of carbon and hydrogen at grain bou daries leads to a significant decrease in th elongation to fracture compared with the carbon-free case. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: cosegregration, simulation & modelling, grain boundary fracture The phenomenon of hydrogen embrittlement (HE) is well-known to a have a significant influence on the mechanical stability of a wide range of metallic systems, leading to potentially catastrophic damage of metallic components. Due to environmental concerns, ther have be n increasing demands on the automob le industry to decrease the body mass of © 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. The phenomenon of hydrogen embrittlement (HE) is well-known to a have a significant influence on the mechanical stability of a wide range of metallic systems, leading to potentially catastrophic damage of metallic components. Due to environmental concerns, there have been increasing demands on the automobile industry to decrease the body mass of 1. Introduction 1. Introduction

* Corresponding author. E-mail address: e.mceniry@mpie.de * Corresponding author. E-mail ad ress: e.mceniry@mpie.de

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452-3216 © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. 2452-3216 © 2018 The Authors. Published by Elsevier B.V. Peer review under r sponsibility of the ECF22 organizers.

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016.

2452-3216  2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. 10.1016/j.prostr.2018.12.231