PSI - Issue 13

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ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com ScienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structu al Integrity 13 (2018) 548–553 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 Improvement of Strength-Toughness Combination in Nanostructured Bainite Avanish Kumar, Aparna Singh * Department of Metallurgical Engineering and M terials Science, Indian Institute of Technology Bombay, Mumbai, 400076, India Abstract The present study makes an effort to improve strength-toughness combination of a high carbon carbide free nanostructured bainite by investigating the effect of content, size and morphology of constituent phases when austempered at 250-350°C. Tension tests showed that the tensile strength increases sharply with refinement of bainitic microstructure with decrease in austempering temperature while retaining significant ductility. However, degradation of toughness was observed with an increase in strength. Processing-microstructure-properties correlations have been formulated in addition to detailed electron microscopy to explain the experimental trends. © 2018 The Aut ors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: Nano-bainite; strength; toughness; phase transformation 1. Introduction The class of high carbon carbide free nanostructured bainitic steels is well known as super-bainite. The microstructure contains nano-scaled bainitic laths immersed in film type retained austenite (Peet et al. 2017; Bhadeshia 2013). The strength f these alloys primarily arises from the dislocation movement interruption by the numerous boundaries of nano-scaled bainite laths. Dislocation density and interface density grows with increasing carbon percentage and decreasing isothermal transformation temperature (Bhadeshia 2010). In most of the cases, the ECF22 - Loading and Environmental effects on Structural Integrity Improvement of Strength-Toughness Combination in Nanostructured Bainite Avanish Kumar, Aparna Singh * Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai, 400076, India Abstract The present study mak s effort to improve strength-t ughness combination of a high carbon carbide free nanostructured bainite by investigating the effect of content, size and morpholo y of constituent phases when austempered at 250-350°C. ension tests showed that the tensile strength increases sharply with refinement of bainitic microstructure with dec ease in austempering t mperature while retaining sig ificant ductility. H wever, degradatio of toughness w s observed with an increase in strength. Processing-microstructure-properties co relations have been formulat d in add tion to detailed electron microscopy to explain the exp rimen al trends. © 2018 The Authors. Published by Elsevier B.V. Peer- eview under respo sibility of the ECF22 organizers. K ywords: Na o-bainite; strength; t ug ness; phase transformation 1. Introduction The class of high carbon carbide free nanostructured bainitic steels is well known as super-bainite. The microstructur contains nano-scal bainitic laths immersed in film type retained austenite (Peet et al. 2017; Bhadeshia 2013). The strength of these alloys primarily arises from the dislocation movement interruption by the numerous boundaries of nano-scaled bainite laths. Dislocation density and interface density grows with increasing carbon percentage and decreasing isothermal transformation temperature (Bhadeshia 2010). In most of the cases, the © 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.: +91-22-2576-7605; fax: +91 22 2572 3480 E-mail address: aparna_s@iitb.ac.in * Corresponding author. Tel.: +91-22-2576-7605; fax: +91 22 2572 3480 E-mail address: aparna_s@iitb.ac.in

2452-3216  2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. 10.1016/j.prostr.2018.12.090

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