PSI - Issue 13

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 Structural Integrity 13 8 39–44 Available online at www.sciencedirect.com Structural Integrity Procedia 00 (2018) 0– 0 Available online at www.sciencedirect.com Structural Integrity 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. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. ECF22 - Loading and Environmental e ff ects on Structural Integrity Damage and fracture of ductile sheet metal: New biaxially loaded specimens for material parameter identification Ste ff en Gerke a, ∗ , Moritz Zistl a , Marco Schmidt a , Michael Bru¨nig a a Institut fu¨r Mechanik und Statik, Universita¨ t der Bundeswehr Mu¨nchen, Werner-Heisenberg-Weg 39, D-85577 Neubiberg, Germany Abstract The paper deals with an experimental series of the new biaxial X0-specimen to study the damage and fracture behavior of ductile sheet metal. The specimens have been fabricated from the aluminum alloy EN AW 6082 (AlSiMgMn) and are proportionally loaded with di ff erent ratios. Firstly di ff erent specimen geometries from the literature for the material parameter determination of sheet metal are discussed and in this context new specimen geometries are motivated and presented. In continuation a corresponding phenomenological con tinuum damage model is briefly introduced. Main focus is given on experimental results with the biaxial X0-specimen whereas results of new load cases are presented and discussed. The geometry indicates good applicability while advantages and disadvan tages a e pointed out and finally a perspective to future work is given. c 2018 The Authors. Publishe by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: Biaxi l experiments; new specimens; ductile damage and fracture; st ess tate dependence; sheet metals; digit l image correlation (DIC); scanning l ctron microscope (SEM) 1. Introduction The damage and fracture behavior of ductile sheet metal depends on the stress state, i.e. the stress intensity, the stress triaxiality and the Lode parameter and is characterized by di ff erent deterioration processes like nucleation of voids, its growth and coalescence or the formation of micro-shear-cracks which lead to final failure of the material. These mechanisms are reflected in the phenomenological continuum damage and fracture model, whereas the identifi cation of the parameters appearing in the constitutive equations and their stress-state-dependence is a big challenge and can not be realized by one-dimensional experiments only. A first estimate has been made based on three-dimensional unit cell model calculations (Bru¨nig et al. (2013, 2014, 2017)) while an experimental validation is still pending. Conse quently, additional experimental data is needed which can be obtained by newly proposed biaxial experiments. In this context a brief overview of specimen geometries discussed in literature with restriction to flat geometries fabricated from metal sheets which are loaded in plane is given, see Fig. 1. ECF22 - Loading and Environmental e ff ects on Structural Integrity Da age and fracture of ductile sheet etal: New biaxially loaded speci ens for aterial para eter identification Ste ff en Gerke a, ∗ , Moritz Zistl a , Marco Schmidt a , Michael Bru¨nig a a Institut fu¨r Mechanik und Statik, Universita¨ t der Bundeswehr Mu¨nchen, Werner-Heisenberg-Weg 39, D-85577 Neubi erg, Germany Abstract The paper deals with an experimental series of the new biaxial X0-specimen to study the damage and fracture behavior of ductile sheet metal. The specimens have been fabricated from the aluminum alloy EN AW 6082 (AlSiMgMn) and are proportionally loaded with di ff erent ratios. Firstly di ff erent specimen geometries from the literature for the m terial parameter determination of sheet metal are discussed and in this context new specimen geometries are motivated and presented. In continuation a corresponding phenomenological con tinuum damage model is briefly introduced. Main focus is given on experimental results with the biaxial X0-specimen whereas results of new load cases are presented and discussed. The geometry indicates good applicability while advantages and disadvan tages are pointed out and finally a perspective to future work is given. c 2018 The Authors. Published by Elsevier B.V. r-review unde responsibility of the ECF22 organizers. Keywords: Biaxial experiments; new specimens; ductile damage and fracture; stress state dependence; sheet metals; digital image correlation (DIC); scanning electron microscope (SEM) 1. Introduction The damage and fracture behavior of ductile sheet metal depends on the stress state, i.e. the stress intensity, the stress triaxiality and the Lode parameter and is characterized by di ff erent deterioration processes like nucleation of voids, its growth and coalescence or the formation of micro-shear-cracks which lead to final failure of the material. These mechanisms are reflected in the phenomenological continuum damage and fracture model, whereas the identifi cation of the parameters appearing in the constitutive equations and their stress-state-dependence is a big challenge and can not be realized by one-dimensional experiments only. A first estimate has been made based on three-dimensional unit cell model calculations (Bru¨nig et al. (2013, 2014, 2017)) while an experimental validation is still pending. Conse quently, additional experimental data is needed which can be obtained by newly proposed biaxial experiments. In this context a brief overview of specimen geometries discussed in literature with restriction to flat geometries fabricated from metal sheets which are loaded in plane is given, see Fig. 1. © 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 ∗ Corresponding author. Tel.: + 49-89-6004-3422. E-mail address: ste ff en.gerke@unibw.de ∗ Corresponding author. Tel.: + 49-89-6004-3422. E-mail address: ste ff en.gerke@unibw.de

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. 2210-7843 c 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. 2210-7843 c 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 responsibility of the ECF22 organizers. 10.1016/j.prostr.2018.12.007