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) 1195–12 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. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. ECF22 - Loading and Environmental effects on Structural Integrity Characterization of J-R curves of a HSLA-steel and anAlloy 52 DMW with SE(T) specimens S. Lindqvist a , T. Seppänen a a VTT, Kemistintie 3, Espoo and 02150, Finland Abstract The J-R curves determined with high constraint specimens can be overly conservative for structural integrity analyses of cracks in pipes and pressure vessels. In this investigation, J-R curves are determined experimentally with low-constraint single edge tension (SE(T)) specimens of a HSLA-steel and an Alloy 52 dissimilar metal weld (DMW) and the quality of the data is analysed. The results show that the CANMET crack length prediction gives a good fit to the measured data within the validity limits of the prediction, the stress in the remaining ligament does not exceed the true tensile strength, and the increase in the J-R curve due to loss of constraint was predicted analytically. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: Dissimilar metal weld; SE(T); Constraint; J-R curve; Tearing resistance; Fracture toughness 1. Introduction Current fracture tough ess standards r commend the use of high constraint, deeply- cracked, compact tension (C(T)) and single-edge bend (SE(B)) specimens to determine the J-R curves, the tearing resistance. Cracks in components, e.g. pipes, are most often surface cracks with low constraint, which contrast to the conservative J-R curves obtained with SE(B) and C(T) specimens. Recent defect assessment procedures recommend the use of J-R curves obtained with single edge tension (SE(T)) specimens where the constraint condition is similar to that of cracks in pipes. In contrast to the benefits of SE(T) specimens, fixture and gripping conditions may cause some experimental challenges raising concerns about the quality of th obtained J-R curves (Mathias et al. 2013). In addition, only few investigations focus on the applicability of SE(T) specimens for heterogeneous materials, like dissimilar metal welds (DMWs). The quality of the J-R curves can be analysed by comparing the measured and predicted crack lengths and compliance. In this study, the J-R curves of a DMW and a high strength low alloy steel (HSLA-steel) is characterised with SE(T) specimens. The quality of the data and the deformation of the ligament is analysed. The J-R curves of the DMW are compared to results obtained with SE(B) specimens of the same material. ECF22 - Loading and Environmental effects on Structural Integrity Characterization of J-R curves of a HSLA-steel and anAlloy 52 DMW with SE(T) specimens S. Lindqvist a , T. Seppänen a a VTT, Kemistintie 3, Espoo and 02150, Finland Abstract The J-R curves determined with high constraint specimens can be overly conservative for structural integrity analyses of cracks in pip s and pres ur vessels. In is investigatio , J-R curves are d termined experimentally with low-constraint singl edge tensio (SE(T)) specimens of a HSLA-steel and an Alloy 52 dissimilar metal weld (DMW) and the quality f the data is analysed. The results show that the CANMET crack length prediction gives a good fit to the measured data within t v lidity limits of t prediction, the stress in the remaining ligament does n t exceed the true tensile strength, and the increase in the J-R curve due to loss of constraint was predicted alytically. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: Dissimilar metal weld; SE(T); Constraint; J-R curve; Tearing resistance; Fracture toughness 1. Introduction Current fracture toughness standards recommend the use of high constraint, deeply- cracked, compact tension (C(T)) and single-edge bend (SE(B)) specimens to determine the J-R curves, the tearing resistance. Cracks in components, e.g. pipes, are most often surface cracks with low constraint, which contrast to the conservative J-R curves obtained with SE(B) and C(T) specimens. Recent defect assessment procedures recommend the use of J-R curves obtained with single edge tension (SE(T)) specimens wher the constraint condition is similar to that of cracks in pipes. In contrast to th be efits of SE(T) specimens, fixture and gripping conditions may cause some experimental challenges raising concerns about the quality of the obtained J-R curves (Mathias et al. 2013). In addition, only few investigations focus on the applicability of SE(T) specimens for heterogeneous materials, like dissimilar metal welds (DMWs). The quality of the J-R curves can be analysed by comparing the measured and predicted crack lengths and compliance. In this study, the J-R curves of a DMW and a high strength low alloy steel (HSLA-steel) is characterised with SE(T) specimens. The quality of the data and the deformation of the ligament is analysed. The J-R curves of the DMW are compared to results obtained with SE(B) specimens of the same material. © 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.

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.2018.12.247