PSI - Issue 6

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at www.sciencedire t.com ScienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structu al Integrity 6 (2017) 196–20 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2017) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2017) 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. Copyright © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the MCM 2017 organizers. XXVII International Conference “Mathematical and Computer Simulations in Mechanics of Solids and Structures”. Fundamentals of Static and Dynamic Fracture (MCM 2017) Strength and fracture of ultrafine-grained titanium Grade 4 Ivan Smirnov a, *, Alexander Polyakov b , Yuri Sudenkov a a Saint Petersburg University, 7/9 Universitetskaya nab., Saint Petersburg, 199034, Russia b Ufa State Aviation Technical University, K. Marx Street 12, Ufa, 450008, Russia Abstract Processing of metallic materials by methods of severe plastic deformation (SPD) provides a possibility to reduce grain sizes to nanocrystalline (NC) or ultrafine-grained (UFG) conditions. Such a structure can lead to high strength of the material, but can also reduce material ductility. The majority of papers on this topic consider deformation parameters of NC and UFG materials only for the case of quasi-static tensile tests. Parameters of fracture toughness, dynamic strength, as well as fracture processes of UFG materials remain poorly understood. However, a reduction in ductility may result in low values of important constructional strength characteristics. This reduces the attractiveness of NC and UFG materials for industrial applications. This work presents the study an influence of SPD on the constructional strength parameters and fracture character of commercially pure titanium Grade 4. The UFG structure of the material was obtained by means of equal-channel angular pressing according to the Conform scheme (ECAP-Conform) and subsequent drawing. The combination of the utilized modes of ECAP and heat treatment makes it possible to obtain the maxi al known degre of ductility for the UFG titanium. Quasist tic tensil tests, impact toughness tests on amples with U-shaped notch, a d fracture toughness test for the case of three-point bendin were carried out. The t st results of the UFG titanium showed an increase in the tensile strength by 40%, an increase in the impact toughness y 15% and a reduction in the fract re toughness by 30% as compared to its coarse-grained analog. Fracture surfac corresponding to loc lized plastic deformation is observed for all of the performed tests. © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of he MCM 2017 organizers. Keywords: sever plastic deformation, ultrafine-grained structure, pure titanium, tensile strength, impact toughness, fracture toughness. XXVII International Conference “Mathematical and Computer Simulations in echanics of Solids and Structures”. Fundamentals of Static and Dynamic Fracture (MCM 2017) Strength and fractu e of ultrafine-grain d titanium Grade 4 Ivan Smirnov a, *, Alexander Polyakov b , Yuri Sudenkov a a Saint Petersburg University, 7/9 Universitetskaya nab., Saint Petersburg, 199034, Russia b Ufa State Aviation Technical University, K. Marx Street 12, Ufa, 450008, Russia Abstract Processing of metallic materials by methods of severe plastic deformation (SPD) provides a po sibility to reduce g ain sizes to nanocrystalline (NC) or u trafine-grained (UFG) conditions. Such a structu e can le d to high str ngth of the material, but can also reduc mat rial ductility. The majori y of pap rs on this topic consid r deformation parameters of NC nd UFG materials only for he case of quasi-static tensile tests. Parameters of fracture toughness, dynamic strength, as well as fracture processes of UFG materials r ma n poorly under tood. Howe r, a reduction in ductility may result in low values of mportant constructio al str ngth characteristi s. This reduces the attractive es of NC and UFG m terials fo industrial applications. This wo k presents the study an influence of SPD on the constructi nal strength p ramet rs nd fracture character of commerc ally pur titaniu Grade 4. The UFG structure of the mat rial was obtain d by me ns of equal-channel angular pressing according to the Conform scheme (ECAP-Conform) and subsequent drawing. The combination of the utilized modes of ECAP and heat treatment makes it possible to ob ain the maximal known degre of ductility f r the UFG titanium. Quasistatic tensile tests, im act toughness tes n samples w h U-shaped notch, a d fractur ough ess test for the case of three-point ben ing were carrie out. The test results of the UFG titanium showed an increase in the tensile strength by 40%, an increase in the impact t ughness by 15% nd a reduction in the fracture toughness by 30% as compared to its coarse-grained analog. Fracture surface corresponding to localized plastic deformation is observed for all of the performed tests. © 2017 The Autho s. Published by Elsevier B.V. Peer-review und r responsibil ty of the MCM 2017 organizers. Keywords: severe plastic deformation, ultrafine-grained structure, pure titanium, tensile strength, impact toughness, fracture toughness.

© 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’s E-mail : i.v.smirnov@spbu.ru * Corresponding author’s E-mail : i.v.smirnov@spbu.ru

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452 3216 © 201 7 Th Authors. Published by Elsevier B.V. Peer-review under responsibility of the MCM 2017 organizers. 2452-3216 © 201 7 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the MCM 2017 organizers.

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016.

2452-3216 Copyright  2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the MCM 2017 organizers. 10.1016/j.prostr.2017.11.030