PSI - Issue 13

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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 13 (2018) 2221–2226 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000 – 000 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 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. ECF22 - Loading and Environmental effects on Structural Integrity Microstructural and fracture analysis of microalloyed steel weld metal R. Prokić Cvetković a , O. Popović a * , R. Jovičić b , N. Milošević a , Z. Burzić c , I. Cvetk vić b a University of Belgrade, Faculty of Mechanical Engineering, Kraljice Marije 16, Belgrade, Serbia b University of Belgrade, Innovation center Faculty of Mechanical Engineering, Kraljice Marije 16, Belgrade, Serbia c Military technical institute, Ratka Resanovi ća 1, Belgrade, Serbia Abstract In this paper is presented behavior of microalloyed steel weld metal with niobium during impact testing, as well as microstructural characterization. Impact tests were done on instrume ted Charpy pendulum at room temper ture at -4 0 C and - 55 0 C. At room temperature, crack propagation energy is much higher than crack initiation energy, while at -40 0 C and -55 0 C crack growth energy is lower than crack initiation energy. Fractographic investigation of the fracture surfaces has shown that at room temperature ductile trans-granular fracture is dominant, with a small amount of brittle trans-granular fracture. At lower temperature, the share of brittle fracture is increased, and inter-granular brittle fracture becomes dominant. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: weld metal; micro-alloyed steel; microstructures; fracture analysis; toughness 1. Introduction Finegrain microalloyed steels have wide field of application in various industries because of their very good mechanical properties. These properties are result of chemical composition and the processing technology that are closely related to the microstructure. Low carbon content provides them to be welded easily without preheating. In the structure of weld metal, besides other microconstituents, is very often present acicular ferrite, which has a positive effect on toughness. Acicular ferrite nucleates within the original austenite grains on inclusions that have complex ECF22 - Loading and Environmental effects on Structural Integrity Microstructural and fracture analysis of microalloyed steel weld metal R. Prokić Cvetković a , O. Popović a * , R. Jovičić b , N. Milošević a , Z. Burzić c , I. Cvetković b a University of Belgrade, Faculty of Mechanical Engineering, Kraljice Marije 16, Belgrade, Serbia b University of Belgrade, Innovation center Faculty of Mechanical Engineering, Kraljice Marije 16, Belgrade, Serbia c Military te hnical institute, R tka Resanovi ća 1, Belgrade, Serbia Abstract In this paper is presented behavior of microalloyed steel weld metal with niobium during impact testing, as well as microstructural characterization. Impact tests were done on inst umented Charpy pen ulum at room temper ture, at -4 0 C and - 55 0 C. At room tem eratur , crack pr pagation energy is much higher than crack initiation energy, while t -40 0 C and -55 0 C crack growth energy is low r than crack initiation e ergy. Fractographic inv stigation of the fracture surfaces has shown that at room tempera ure ductile trans-granular fracture is dominant, with a small amount of brittl trans-granular fracture. At lower temperature, the share of brittle fracture is i creased, and inte -granular br ttle fracture becomes dominant. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. K ywords: eld metal; micro-alloyed steel; microstructures; fracture analysis; toughness 1. Introduction Finegrain microalloyed ste ls have wid field of application in various industries because of their v ry good mechanical properties. These properties are result of chemical composition and the processing technology that are closely related to the microstructure. Low carbon content provides them to be welded easily without preheating. In the structure of weld metal, besides other microconstituents, is very often present acicular ferrite, which has a positive effect on toughness. Acicular ferrite nucleates within the original austenite grains on inclusions that have complex © 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 responsibility of the ECF22 organizers. * Corresponding author. Tel.: +381113302-259 E-mail address: opopovic@mas.bg.ac.rs * Corresponding author. Tel.: +381113302-259 E-mail address: opopovic@mas.bg.ac.rs

2452-3216  2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. 10.1016/j.prostr.2018.12.137

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