PSI - Issue 10

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 Structural Integrity 1 8 49–58 Available online at www.sciencedirect.com ScienceDirect 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 Th Authors. P blished by Elsevier Ltd. This is an open access article under the CC BY-NC-ND lice se (http://creativecommons.org/licenses/by-nc-nd/3.0/) Peer-review under responsibility of the scientific committee of the 1st International Conference of the Greek Society of Experimental Mechanics of Materials. 1 st International Conference of the Greek Society of Experimental Mechanics of Materials The impact of corrosion and inelastic buckling on low cycle fatigue life of steel bars Alk. Apostolopoulos*, T. Matikas Department of Material Science and Engineering, University of Ioannina, Greece Abstract The current experimental study examines the effect of corrosion damage and inelastic buckling on low cycle fatigue (LCF) life of reinforcing steel bars grade B500A and B500B, with nominal diameter of 12 mm. In a total of 110 specimens, experimental tests were conducted before and after exposure in laboratory salt spray environment. The results of LCF tests on corroded reinforcing bars varied in mass loss percentage, strain amplitudes and buckling lengths. The results of mechanical tensile tests confirmed that cor rosion is a significant factor of degradation in mechanical properties of steel bars. The percentage mass loss, the pitting corrosion and the inelastic buckling constitute the main parameters of affecting negatively the (seismic behavior) low-cycle fatigue life of the steel bars. Additionally, a reduction to the number of cycles to failure under conditions of low cycle fatigue was recorded. The findings also sug est that th degradati n of the mechanical perf rma ce of ste l on s ismic loads can be attributed to mechanism of inelastic buckling influenced by history of loads combine with the presence of ext nsive porosity close t the surface of the steel bar. © 2018 Th e Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). Peer-review under responsibility of the scientific committee of the 1 st International Conference of the Greek Society of Experimental Mechanics of Materials Keywords: Steel Bars B500A and B500B; salt spray corrosion; low cycle fatigue; degradation of service life e e e Authors. Published by Elsevier Ltd. t als Keywords: Steel Bars B500A and B500B; salt spray corrosion; low cycle fatigue; degradation of service life

1. Introduction

© 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 effects of seismic action (seismic loads) are known to act on the load bearing elements of structures in the form of high strain reversals, which is commonly simulate as single axis LCF. The investigation of the devastating

* Corresponding author. Tel. +30 698 4122579 E-mail address: alkiviadisapostolopoulos@gmail.com Received: July 09, 2018; Received in revised form: July 30, 2018; Accepted: August 8, 2018

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 Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/) Peer-review under responsibility of the scientific committee of the 1st International Conference of the Greek Society of Experimental Mechanics of Materials. 10.1016/j.prostr.2018.09.008 2452- 3216 © 2018 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). Peer-review under responsibility of the scientific committee of the 1 st International Conference of the Greek Society of Experimental Mechanics of Materials i st * Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt