PSI - Issue 8

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedirect.com cienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structu al Integrity 8 (2018) 239–255 Available online at www.sciencedirect.com ScienceDirect Structural Int grity Procedia 00 (2017) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2017) 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. Copyright © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of AIAS 2017 International Conference on Stress Analysis AIAS 2017 International Conference on Stress Analysis, AIAS 2017, 6-9 September 2017, Pisa, Italy Tribological characterization of modified polymeric blends Massimiliano Avalle a, *, Elisa Romanello b a Università degli Studi di Genova, Via all’Opera Pia 15, 16145 Genoa, Italy b Politecnico di Torino, Sede di Alessandria, Viale Teresa Michel 5, 15121 Alessandria, Italy Abstract The present work reports of a series of experimental tests with two polymeric materials, a thermoplastic polyurethane (TPU) and a polyamide (PA), modified with the inclusion of additives, in terms of their tribological properties of friction and wear. Many thermoplastic materials are in fact used in applications with s liding contact and friction (as in journal bearings, supports…) and, to improve their properties, the polymer is modif ed with additives having the capacity to change the surface properties. Used additives are of several types: in this work a comparison is made between graphite, polytetrafluoroethylene, a silicone (siloxane), molybdenum disulfide, and carbon nanotubes. For each additive, different percentage in weight have been considered. All these materials can modify the surface properties of the base material exploiting different physical and chemical phenomena. Moreover, the presence of such additives can alter the mechanical properties of the materials sometimes reducing stiffness, strength, and strain limit. The work reports of the experimental methods obtained with a typical tribological test (pin-on-disk method) to measure the tribological properties of the compounds in terms of friction and wear, together with mechanical tests. The analysis will show correlations between the composition, in terms of type and quantity of the additive, on the properties of the compounds. © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific C mmittee of AIAS 2017 Inter ational Conferenc on Stre s Analysis. Keywords: thermoplastic materials; wear; friction AIAS 2017 International Conference on Stress Analysis, AIAS 2017, 6-9 September 2017, Pisa, Italy Tribological characterization of modified polymeric blends Massimiliano Avalle a, *, Elisa Romanello b a Università degli Stu di Genova, Via l’Oper Pia 15, 16 45 Genoa, Italy b Politecnico di Torino, Sede di Alessandria, Viale Teresa Michel 5, 15121 Alessandria, Italy Abstract The present work reports of a series of experiment l tests with two polymeric materials, thermoplastic polyurethane (TPU) and a polyamide (PA), modified with the inclusion of additives, in terms of their tribol gic l properties of friction and wear. Many thermoplastic materials are in fact used in applications with s liding co tact a d f iction (as n j urnal bearings, supports…) and, t improve their properties, the pol mer is modified with additives having th capacity to change the surface pr perties. Used additives are of several types: in this work a comparison is made betw en graphite, polytetrafluoroethylene, a silicone (siloxan ), molybdenum disulfide, and carbon nanotubes. For each dditiv , different percentage in weight have been considered. All thes materials can modify the surface properties of t e base mat rial exploiting different physical and chemical phenomena. Moreover, the presence of such additives can alter the mechanical properties of the materials sometimes reducing stiffness, strength, and strain limit. The work reports of the experi ental methods obtained with a typical tribological test (pi -on-disk method) to measure the tribological properties of the compounds in terms of friction and wear, together with mechanical tests. The analysis will show correlations between the composition, in terms of type and quantity of the additive, on the properties of the compounds. © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of AIAS 2017 International Conference on Stress Analysis. Keywords: thermoplastic materials; wear; friction

© 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.: +39-010-3532241; fax: +39-010-3532834. E-mail address: massimiliano.avalle@unige.it * Correspon ing author. Tel.: +39-010-3532241; fax: +39-010-3532834. E-mail address: massimiliano.avalle@unige.it

2452-3216 © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of AIAS 2017 International Conference on Stress Analysis. 2452 3216 © 2017 Th Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of AIAS 2017 International Conference on Stress Analysis.

* 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 PCF 2016.

2452-3216 Copyright  2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of AIAS 2017 International Conference on Stress Analysis 10.1016/j.prostr.2017.12.026