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) 1855–186 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural I t grity 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. ECF22 - Loading and Environmental effects on Structural Integrity Evaluation of bending fatigue strength in automotive gear steel subjected to shot peening techniques. R.D. Lambert a, *, C.J. Aylott a , B.A. Shaw a a Design Unit, School of Engineering, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK Abstract The effect of residual stress is known to have a large influence on the integrity of engineered components including gears. Shot peening is a popular process used to introduce compressive residual stresses into a material which are beneficial to their fatigue life. Bending fatigue failure of gears is one of a number of failure modes a gear designer must account for and which can cause catastrophic failure of a gearbox. This paper presents results from the Innovate UK funded ULTRAN project to demonstrate the effects of a number of different shot peening processes upon the bending fatigue strength of an automotive gear steel. Results to be presented include residual stress measurements, bending fatigue results from pulsator tested gears and a study of the fatigue crack growth in the material. Four different shot peening techniques are presented along with baseline data. Whilst there was a large change in bending fatigue strength between the as-carburised and shot peened samples, the changes in residual stress caused by the optimised and the duplex shot peening methods did not correspond to a similarly dramatic increase in fatigue strength. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: Gears; bending fatigue; residual stress; shot peening; fracture. 1. Introduction The design of gears is often particularly focused on reducing failures due to fatigue processes. The gear designer has control over a number of material and geometrical factors which can be used to improve fatigue life. With the increasing importance of vehicle efficiency and tighter controls on emissions, there is a significant drive within the automotive industry to improve gearbox design and allow increases in efficiency and reductions in weight. To this © 2018 Th Authors. P blished by Elsevier B.V. Peer-review und responsibility of the ECF22 organizers. ECF22 - Loading and Environmental effects on Structural Integrity Evaluation of bending fatigue strength in automotive gear steel subj cted to shot peening techniques. R.D. Lambert a, *, C.J. Aylott a , B.A. Shaw a a Design Unit, School of Engineering, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK Abstract The effect of residual stress is known to have a large influence on the integrity of engineered components including gears. Shot peening is a p pular process used to introduce compressive residual stresses into a material which are benefi ial to their fatigue life. Bending fatigue failure of gears is one of a number of failure mod a gear design r must account for and whic can caus catastrophic failure of gearbox. This paper presents results from the Innovate UK funded ULTRAN project to demonstrate the effects of a number of different shot peening proc sses upon the bending fatigue strength of an automotive gear steel. Results to be presented incl de residual str ss measur ments, bending fatigue results from p lsator tested gears and a study of the fatig e crack growth in the material. Four different shot peening techniques are presented along with baseline data. Whilst there was a large ch nge in bending fatigue strength between the as-carburised and shot peened samples, the changes in residual str ss cau ed by the optimised and the duplex hot peening methods did not correspond to a similarly dramatic increase in fatigue strength. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: Gears; bending fatigue; residual stress; shot peening; fracture. 1. Introduction The design of gears is often particularly focused on reducing failures due to fatigue processes. The gear designer has control over a number of material and geometrical factors which can be used to improve fatigue life. With the increasing importance of vehicle efficiency and tighter controls on emissions, there is a significant drive within the automotive industry to improve gearbox design and allow increases in efficiency and reductions in weight. To this © 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.: +44 191 208 6280; E-mail address: robert.lambert@ncl.ac.uk * Corresponding author. Tel.: +44 191 208 6280; E-mail address: robert.lambert@ncl.ac.uk

* 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 o ganizers.

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.2018.12.329