PSI - Issue 13

ScienceDirect Available online at www.sciencedirect.com Av ilable o line at ww.sciencedire t.com Sci ceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structu al Integrity 13 (2018) 198–2 3 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000 – 000 il l li t . i i t. tr t r l I t rit r i ( )

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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 Prediction of steel weld HAZ Charpy impact property based on stochastic fracture model incorporating microstructural parameters Michihiro Kunigita a , Kengo Tanaka a , Tomoya Kawabata a , Tadashi Kasuya a , Yoshiomi Ok zaki b , Masahiro Inomoto b and Shuji Aihara a a The University of Tokyo, 7-3-1, Hongo, Bunkyo, Tokyo, 113-8656, Japan b Kobe Steel Ltd., 2222-1, Onoecho Ikeda, Kakogawa, Hyogo, 675-0023, Japan The present study proposed a model to predict Charpy impact absorbed energy for steel weld HAZ of predominantly upper bainite containing martensite-austenite constituent (MA) as a second phase. Probability distribution of local fracture stress for cleavage crack nucleation is calculated from microstructural parameters. On the other hand, local stress and strain are calculated from dynamic elastic-plastic finite-element analysis. Applying the weakest-link mechanism, probability of cleavage fracture is calculated. Charpy impact tests were conducted for steel simulated HAZ with various cooling rates. As a resu t, the predicte Charpy absorbed energy transition curves agreed well with the xperiment and the model was validated. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. Keywords: toughness; steel; weld heat-affected zone; fracture mechanics; modelling Prevention of brittle fracture is one of the most important issues in maintaining reliability of welded steel structures. Welds are most probable parts of brittle fracture initiation because they might contain defects and have local brittle zones. There have been many studies on the toughness of weld heat-affected zone (HAZ) and microstructures influencing HAZ toughness are well known, like effective grain-size of bainite and brittle microphases. But, most of the studies are not based on the theories but simply correlating toughness data with microstructural parameters. The present study is aiming at establishing a theoretical model to describe cleavage fracture and proposing a model to predict Charpy impact property of steel weld HAZ, based on the local fracture stress criterion together with the weakest link mechanism. Experiments are conducted to validate the proposed model. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. s a a om a a a b b a a i it f , - - , , , , - , b t l t ., - , I , , , - , Abstract t t l t i t i t t l l i tl i it t i i t it t it tit t . ilit i t i ti l l t t l l ti i l l t i t t l t . t t , l l t s t i l l t i l ti l ti i it l t l i . l i t t li i , ilit l t i l l t . i t t t t t l i l t it i li t . lt, t i t d t iti ll it t i t t l li t . © 2018 The Authors. ublished by l i . . i i ilit t i . : t ; t l; l t- ff t ; fr t r i ; elling . i ti ittl t i t t i t t i i i t i i li ilit l t l t t . l t l t ittl t i iti ti t i t t i t l l ittl . t i t t l t t i t t i l i t ll , li ti i i i it ittl i . t, t t t i t t t i t i l l ti t t it i t t l t . t t i i i t t li i t ti l l t i l t i l t i t i t t t l l , t l l t t it i t t it t t li i . i t t t li t t l. © 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. Abstract 1. Introduction

* 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. t r . li l i r . . i i ilit t i . -

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.2018.12.033