PSI - Issue 2_A

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 Structu al Integrity 2 (2016) 769–776 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2016) 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. 21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy Analysis of specimen size conversion in the ductile to brittle transition region of ferritic steels Juan E. Perez Ipiña a, *, Carlos Berejnoi b a Grupo Mecánica de Fractura, Universidad Nacional del Comahue / CONICET, calle Buenos Aires 1400, Neuquén (8300), Argentina. b Facultad de Ingeniería, Universidad Nacional de Salta / CIUNSa, Avda. Bolivia 5500, Salta (4400), Argentina. Abstract The ASTM E 1921-15 standard covers the determination of the Master Curve, a function used to characterize the fracture toughness of ferritic steels that experience onset of cleavage fracture in the transition region. In the standard, the specimen size effect on fracture toughness at cleavage ( K Jc ) in the transition range is explained by the weakest-link theory, using a three parameter Weibull distribution with shape (b) and threshold ( K min ) parameters fixed. When specimens from different sizes are tested, a K Jc conversion is necessary. The effect of size conversion using either the equation given by the standard and a three parameter Weibull distribution with the parameters estimated from data sets are compared in this work. It was found that the distributions obtain d from results converted to one-inch siz did not ad us the data in the way the weakest link model would pr dict, meaning that th tatistical ffect due to the difference in the crack front volume would not be the only responsible for the difference in results for different specimen sizes. This was found using both the ASTM E1921 method and the thr e parameter Weibull distribution. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. Keywords: ductile-to-brittle; specimen size conversion; Weibull; Master Curve 1. Introduction The characterization of fractur resistance of ferri ic steels in the ductile- -brittle transition region is problematic due to scatter in results, as well as size and temperature dependences. Copyright © 2016 The Authors. Published by Elsevi r B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the Scientific Committee of ECF21. © 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.: +54-299-4490355; fax: +54-299-4490355. E-mail address: juan.perezipina@fain.uncoma.edu.ar

* 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 ECF21.

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Copyright © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ). Peer review under responsibility of the Scientific Committee of ECF21. 10.1016/j.prostr.2016.06.099