PSI - Issue 14

ScienceDirect Available online at www.sciencedirect.com Available online at www.sciencedirect.com Sci ceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structu al Integrity 14 (2019) 41 –415 ScienceDirect Structural Integrity Procedia 00 (2018) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000 – 000

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2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. 2452-3216  2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. 10.1016/j.prostr.2019.05.050 2452-3216 © 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. 2452-3216 © 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. 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. © 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. 2nd International Conference on Structural Integrity and Exhibition 2018 Stress Rupture Studies of V-notched Grade 92 Steel for High Temperature Applications Ashish Vaidya*, Atul Ballal, Hari Krishan Yadav, Dilip Peshwe Dep rtment of Metallurgical & Materials Engineer ng, VNIT, Nagpur – 440010, India Abstract In the present study, grade 92 steel blanks were subjected to normalizing (1080 °C / 1 hr.) and tempering (780 °C / 1 hr.) followed by air cooling. Stress ruptur tests were performed using start testing systems' uni-axial creep testing machines. The specimens used were circumferential 60° V-notch specimens with notch depth of 0.5, 1.0 and 2.0 mm. The test temperature was 650 °C and net applied stress level was 195 MPa. Notch strengthening effect was observed in grade 92 steel due to generation of tri-axial state of stress at the notch root. Post-creep characterization included scanning electron micrography of creep fractured samples which showed mixed mode of fracture. The fracture at area near the notch root was dominated by brittle fracture whereas the one near the center of the specimen was dominated by ductile fracture. Brittle mode of fracture was attributed to the mechanical constraint at the notch root and ductile fracture developed following creep cavitations and micro-void coalescence. © 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. Keywords: Grade 92 steel; heat treatment; V-notch; creep; notch strengthening; fracture 1. Introduction Creep resistant grade 92 steel is one of the candidate materials for structural components of nuclear reactors in India. The important application of grade 92 steel includes piping for pressurized steam carrier, tubing in reheater 2nd International Conference on Structural Integrity and Exhibition 2018 Stress Rupture Studies of V-notched Grade 92 Steel for High Temperature Applications Ashish Vaidya*, Atul Ballal, Hari Krishan Yadav, Dilip Peshwe Department of Metallurgical & Materials Engineering, VNIT, Nagpur – 440010, India Abstract In the present study, g ade 92 stee blanks were ubject d to normalizing (108 °C / 1 hr.) and temp ring (780 °C / 1 hr.) followed by air cooling. Stress rupture tests were perform d usi g start testing syst ms' u i-axial creep testing machines. The specimens used were circumferential 60° V-notch specimens with notch depth of 0.5, 1.0 and 2.0 mm. The test temperature was 650 °C and net applied stress level was 195 MPa. Notch strengthening eff ct was observed in gr de 92 steel ue to gen ration of tri-axi l state of stress at the notch root. Post-creep characterization inc uded scanning electron mic ography of creep fractured samples which showed mixed mode of fractur . The fractur at area near the not h root was do nated by brittle fracture whereas the one near the center of the specimen was dominated by ductile fracture. Brittle mode of fracture was attributed to the mechanical constraint at the notch root and ductile fracture developed following creep cavitations and micro-void coalescence. © 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) S lection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. Keywords: Grade 92 steel; heat treatment; V-notch; creep; notch strengthening; fracture 1. Introduction Creep r sistant grade 92 s eel is one of the candidat materials for structural components of nuclear reactors in India. The important application of grade 92 steel includes piping for pressurized steam carrier, tubing in reheater © 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 * Corresponding author. Tel.: +91-712-2801517 E-mail address: aovaidya@students.vnit.ac.in * Corresponding author. Tel.: +91-712-2801517 E mail address: aovaidya@student .vnit.ac.in