PSI - Issue 13

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at www.sciencedire t.com cienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structural Integrity 13 (2018) 2227–2232 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. ECF22 - Loading and Environmental effects on Structural Integrity Low and high cycle fatigue assessment of mismatched load-carrying cruciform joints Wei Song a,b , Xuesong Liu a, * , Filippo Berto b a State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001, China b Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway Abstract Fatigue behaviors of load-carrying cruciform joints considering geometry variations and strength heterogeneity between base metal and weldments were studied. Low and high cycle fatigue tests were performed on specimens under displacement controlled and force controlled conditions. Observation of the specimens revealed that crack propagation paths differ by different loading conditions and that failure life was dominated by crack propagation. Besides, it was found that the effect of the strength under matching on the fatigue strength becomes large in low cycle fatigue region by signific ntly reducing fatigue life of the specime . The test dat were also assesse by nominal strain and opos d design guidance based on effective notc train. © 2018 The Authors. Published by Elsevier B.V. Peer-review und r responsibility of the ECF22 organizers. Keywords: Low cycle fatgiue; load-carrying cruciform joints; material ismatch; effective otch strain. 1. Introduction In the process of fatigue failure of welded components, fatigue crack usually initiates from stress concentration locations, like weld toe, weld root or inside defeats. The notch effect in engineering structures is one of the most common cause of low cycle or high cycle fatigue failure. Generally, high cycle fatigue life assessment of welded joints is commonly based on nominal, structural stress, notch stress approaches by D. Radaj et al. (2006, 2009). © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. ECF22 - Loading and Environmental effects on Structural Integrity Low and high cycle fatigue assessment of mismatched load-carrying cruciform joints Wei Song a,b , Xuesong Liu a, * , Filippo Berto b a State Key Laboratory of Advanced Weldi g and Joining, Ha bin I stitut of Tech ology, Harbin 150001, China b Department of Mechanical and Industrial E gineering, Norwegia University of Sc ence and Technology (NTNU), 7491 Trondheim, Norway Abstract Fatigue behaviors of load-carrying cruciform joints considering geometry variations and strength heterogeneity between base metal and weldme ts were studied. Low and high cycle fatigue tests were performed on specimens under displace nt controlled a d forc controlled conditions. Observation of the sp cim ns revealed that crack propagation paths differ by different loading c nditions and that failure life was dominated by crack prop gation. Besides, it was found that the eff ct of the stre gth under matching on the fatigue strength ecomes large in l w cycle fatigue regio by significantly reducing fatigue life of the specimen. The te t data w re also ssessed by nominal stra n and pr posed design guida e based o ffective notch strain. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of th ECF22 organizers. Keywords: Low cycle fatgiue; load-carrying cruciform joints; material mismatch; effective notch strain. 1. Introduction In the process of fatigue failure of welded components, fatigue crack usually initiates from stress concentration locations, like weld toe, w ld root or inside defeats. The notch effect in engineering structures is one of the m st c mmon cause of low cycle or high cycle fatigue failur . Generally, high cycl fatigue life asse sment of welded j ints is commonly based o nominal, structural stress, notch str ss approaches by D. Radaj et l. (2006, 2009). © 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.: +86-451-86418433. E-mail address: liuxuesong@hit.edu.cn. * Corresponding author. Tel.: +86-451-86418433. E-mail ad ress: liuxuesong@hit.edu.cn.

* 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.2018.12.136