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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. 21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy Experimental and numerical investigation on relationship between grain size and arrest toughness in steels Takuhiro Hemmi 1 , Kazuki Shibanuma 1 Katsuyuki Suzuki 2 , Shuji Aihara 1 , Hiroyuki Shirahata 3 1 Department of Systems Innovation, The University of Tokyo 2 Research into Artifacts, Center for Engineering, The University of Tokyo 3 Oita R&D Lab, Nippon Steel & Sumitomo etal Corporation Abstract Today, steel plates of container carriers become thicker because larger ships are needed for c rrying more baggage and reducing the transportation cost. Thus, even though brittle fracture occurs, arresting the crack is essential as “double integrity” for structures. It is directly effective to improve the arrest toughness, which is the material resistance against the brittle crack propagation. However, there was not established theory to explain the dependence of the microstructure on arrest toughness. In particular, although it is empirically known that of the finer grain size makes higher crack arrest toughness, the quantitative relationship was not clarified. Recently, Shibanuma et al. proposed a multiscale model to simulate the brittle crack propagation/arrest behaviour qualitatively. However, the microscopic energy absorbing mechanism in the model is too simple to reveal quantitative prediction of arrest toughness. According to the above background, we conduct an experiment to quantitative clarify the relationship between arrest toughness and grain size, and then modify the above multiscale model based on the experimental results. Consequently, the results obviously shows the relationship between arrest toughness and grain size of steels. The experimental result was contrary to the result of microscopic model. Thus, it is necessary to correct a numerical expression of the microscopic energy absorbing mechanism in the model to accurately simulate the actual brittle crack propagation and arrest behavior in steel of arbitrary grain size. 21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy Experimental and numerical investigation on relationship between grain size and arrest toughness in steels Takuhiro Hemmi 1 , Kazuki Shibanuma 1 Katsuyuki Suzuki 2 , Shuji Aiha a 1 , Hiroyuki Shirahata 3 1 Department of Syst ms Innovatio , The Univ rsity of Tokyo 2 Research into Artifacts, Center for Engineering, Th University of Tokyo 3 Oita R&D Lab, Nippon Steel & Sumitomo Metal Corporation Abstract Today, steel plates of container carriers become thicker because larger s ips re needed for c rrying more baggage and reducing the transportation cost. Thus, even though brittle fracture occurs, arresting the crack is essential as “double int grity” for structures. It is directly effective to improve the arrest toughness, which is the material resistance against the brittle crack propagation. However, there was not established theory to explain th dependence of the microstr ctur on arrest toughn ss. In particular, although it is empirically known that of the finer grain size makes higher crack arrest toughness, the quantitative relationship was not clarified. Recently, Shibanuma et al. proposed a multiscale model to simulate the brittle crack propag tion/arrest behaviour qualitatively. Howev r, the microscopic energy absorbing mechanism in the model is too simple to reveal quantitative prediction of rr t t . According to the above background, w condu t an exp riment to quantitative clarify the relationship between arrest toughness and grain size, and then modify the above multisc le model based on the experimental results. Consequently, the results obviously sh ws the relations ip betwe n arrest toughness and grain size of steels. The experimental result was contrary to the result of microscopic model. Thus, it is necessary to correct a numerical expression of the microscopic energy absorbing mechanism in the model to accurately simulate the actual brittle crack propagation and arrest behavior in steel of arbitrary grain size. Copyright © 2016 The Authors. Pub ished by Elsevier B.V. This is an open access ar icle under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the Scientific Committee of ECF21. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. © 2016 The Autho s. Publ shed by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. Keywords: High Pressure Turbine Blade; Creep; Finite Element Method; 3D Model; Simulation. Keywords: brittle fracture, cleavage fracture, multiscale model, crack propagation, crack arrest, arrest toughness, grain size, three-point bending tests, FEM (Finite element analysis) Keywords: brittle fracture, cleavage fracture, multiscale model, crack propagation, crack arrest, arrest toughness, grain size, three-point bending tests, FEM (Finite element analysis)

* Corresponding author. Tel.: +81-3-5841-6554 E-mail address: henmi@struct.t.u-tokyo.ac.jp * Corresponding author. Tel.: +81-3-5841-6554 E-mail address: henmi@struct.t.u-tokyo.ac.jp

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21. 2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ECF21.

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Copyright © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ). Peer review under responsibility of the Scientific Committee of ECF21. 10.1016/j.prostr.2016.06.279