PSI - Issue 13

ScienceDirect Available online at www.sciencedirect.com Available online at ww.sciencedire t.com ienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structural Integrity 13 (2018) 1739–1744 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural I t gri y 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 Influence of additional vibration impact on kinetics of strain bands due to the Chernov-Lüders deformation and Portevin-Le Chatelier ffect in metals Tatyana Tretyakova a *, Ekaterina Zubova a a Centre of Experimental Mechanics, Perm National Research Polytechnic University, 29 Komsomolsky AVE, Perm 614990, Russia Abstract The aim of the work is to investigate the influence of additional vibration impact on spatial-time inhomogeneity of plastic flow due to the Chernov-Lüders deformation and Portevin-Le Chatelier effect in metals (carbon steel and Al Mg alloy) during uniaxial tension tests. Experimental data were obtained (diagrams, evolution of strain fields and local deformation rates, temperature fields, AE parameters) characterizing the kinetics of the strain bands initiation and propagation. The evolution of inhomogeneous strain and temperature fields were analyzed by using the digital image correlation technique and the infrared thermography accordingly. The mechanical behavior and the regularities of the jerky flow were studied using analysis of stress serrations and the accompanying acoustic emission. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: jerky flow; strain band; digital image correlation; thermography; acoustic emission; additional vibration impact. 1. Introduction Many engineering metals and alloys exhibit irregular plastic deformation during uniaxial tension. Instabilities in plastic flow and strain localizations observed only in a given set of conditions (loading regime, strain rate, temperature, chemical composition, etc.). Effects of serrated yielding lead to a significant decrease of strength and plasticity, and reduce the material surface quality. The spontaneous macroscopic localization of plastic flow causes a non-uniform © 2018 The Auth rs. Published by Els vier B.V. Peer-revi w under responsibility of the ECF22 or anizers. ECF22 - Loading and Environmental effects on Structural Integrity Influence of additional vibration impact on kinetics of strain bands due to the Chernov-Lüders deformation and Portevin-Le Chatelier effect in metals Tatyana Tretyakova a *, Ekaterina Zubova a a Centre of Experimental Mechanics, Perm National Research Polytechnic University, 29 Komsomolsky AVE, Perm 614990, Russia Abstract The aim of the work is to investigate the influence of additional vibration impact on spatial-time inhomogeneity of plastic flow due t the Ch rnov-Lüders deformation and Portevin-Le Chateli r effect in metals (carbon steel and Al Mg alloy) during uniaxial tension tests. Experime tal data were obtained (diagrams, evolution of strain fields and local deformation rates, temperature fields, AE parameters) characterizing the kinetics of the strain bands initiation and propagation. The evolution of inhomogeneous strain and temperature fields were analyzed by usi g the digital image correlation technique and the infrared thermography accordingly. The mechanical behavior and the regularities of the jerky flow were studied using analysis of stress serrations and the accompanying acoustic emission. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: jerky flow; strain band; digital image correlation; thermography; acoustic emission; additional vibration impact. 1. Introduction Many engineering metals and alloys exhibit irregular plastic deformation during uniaxial tension. Instabilities in plastic flow and strain localizations observed only in a given set of conditions (loading regime, strain rate, temperature, chemical composition, etc.). Effects of serrated yielding lead to a significant decrease of strength and plasticity, and reduce the material surface quality. The spontaneous macroscopic localization of plastic flow causes a non-uniform © 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 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. * Corresponding author. Tel.: +7-912-499-59-60; fax: +7-342-219-8732. E-mail address: cem.tretyakova@gmail.com * Corresponding author. Tel.: +7-912-499-59-60; fax: +7-342-219-8732. E-mail ad ress: cem.tretyakova@gmail.com

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.2018.12.365