PSI- Issue 9

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 P o edi Structural Integr ty 9 (2018) 71–85 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000–000

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

www.elsevier.com/locate/procedia

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 Gruppo Italiano Frattura (IGF) ExCo. IGF Workshop “Fracture and Structural Integrity” Failure Mechanisms and Modeling of Spot Welded Joints in Low Ca bon Mild Sh ets Steel and High Strength Low Alloy Steel Tareq Rahman Mahmood a , Qasim M. Doos a , A.M. AL-Mukhtar b* a Department of Mechanical Engineering, University of Baghdad, Baghdad, Iraq b TU Freiberg, 09599 Freiberg, Germany Abstract Resistance spot welding process (RSW) is one of remarkable manufacturing processes in automotive industry. There are several process parameters; quantum of weld current, weld time, and electrode force which affect the weld nugget formation and its strength. Therefore, it is necessary to optimize the process parameters of RSW. In this paper spot welded joints of similar sheets thickness have been welded. The tensile specimens have been made according to AWS standard. The optimal parameters for welding machine are evaluated by using Design Expert Program. The tensile shear tests presented three failure modes, interfacial, partial interfacial and pullout failure. These modes related to diversity metallic composition of each steel type and the variance of the sheet thickness. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo. Keywords: Design expert; Failure mechanism; Fracture; Fracture surface; Spot welding 1. Introduction Resistance spot welding process (RSW) for connection sheet metal components has a wide range of applications. The weld nugge between th two sh ets determines the joint performance. RSW is an inexpensive and effective way to join metal she ts (Mirsalehi and Kokabi 2010)(Wang, Wang, and Zhang 2013)(Balasubramanian and Balasubramanian 2010)(Cui et al. 2017). It has an excellent benefits such as low cost, high speed and suitability for IGF Workshop “Fracture and Structural Integrity” Failure Mechanisms and Modeling of Spot Welded Joints in Low Carbon Mild Sheets Steel and High Strength Low Alloy Steel Tareq Rahman Mahmood a , Qasim M. Doos a , A.M. AL-Mukhtar b* a Department of Mechanical Engineering, Unive sity of B ghdad, Baghdad, Iraq b TU Freiberg, 09599 Freiberg, Germany Abstract Resistance spot welding process (RSW) is o e of remarkable manufacturing processes in automotive industry. There are several process parameters; quantum of weld current, weld time, and electrode force which affect the eld nugget f rmation and its strength. Ther for , it is n cessary to optimize th process parameters of RSW. In this paper spot welded joints of similar sheets thickness have been welded. The tensile specimens have been made according to AWS standard. The optimal parameters for welding machine re evaluated by using D sign Expert Program. The tensile shear tests present d thre failure modes, interfacial, partial interfacial and pullout failure. These modes related to diversity metallic composition of each steel type and the variance of the sheet thickness. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of th Gruppo Itali no Frattura (IGF) ExCo. Keywords: Design expert; Failure mechanism; Fracture; Fracture surface; Spot welding 1. Introduction Resistance spot welding process (RSW) for connection sheet metal components has a wide range of applications. The weld nugget between the two s eets determines the j int performance. RSW is an inexpensive and effective way to join metal sheets (Mirsalehi and Kokabi 2010)(Wang, Wang, and Zhang 2013)(Balasubramanian and Balasubramanian 2010)(Cui et l. 2017). It has an excellent benefits such as low cost, high speed and suitability for © 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, Tel: +964 7700381353 E-mail address: almukhtar@hotmail.de * Corresponding author’s, Tel: +964 7700381353 E-mail address: almukhtar@hotmail.de

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 Gruppo Italiano Frattura (IGF) ExCo. 10.1016/j.prostr.2018.06.013 * Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt 2452 3216 © 2018 Th Authors. Published by Elsevier B.V. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo. 2452-3216 © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo.