PSI - Issue 13

ScienceDirect Available online at www.sciencedirect.com Available online at ww.sciencedire t.com cienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structural Integrity 13 (2018) 1427–1432 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural I t gri y Procedia 00 (2018) 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. ECF22 - Loading and Environmental effects on Structural Integrity Tracking hydrogen embrittlement using short fatigue crack behavior of metals Vishal Singh, Rajwinder Singh, Amanjot Singh, Dhiraj K. Mahajan* Ropar Mechanics of Materials Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Ropar, Rupnagar, Punjab, India, 140001 Abstract Understanding hydrogen embrittlement phenomenon that leads to deterioration of mechanical properties of metallic components is vital for applications involving hydrogen environment. Among these, understanding the influence of hydrogen on the fatigue behaviour of metals is of great interest. Total fatigue life of a material can be divided into fatigue crack initiation and fatigue crack growth phase. While fatigue crack initiation can be linked with the propagation of short fatigue cracks, the size of which is of the order of grain size (few tens of microns), that are generally not detectable by conventional crack detection techniques applicable for the long fatigue crack growth behaviour using conventional CT specimens. Extensive literature is available on hydrogen effect on long fatigue crack growth behaviour of metals that leads to the change in crack growth rate and the threshold stress intensity factor range ( ∆ �� ). However, it is the short fatigue crack growth behaviour that provides the fundamental understanding and correlation of the metallic microstructure with hydrogen embrittlement phenomenon. Short fatigue crack growth behaviour is characteristically different from long crack growth behaviour showing high propagation rate at much lower values than threshold stress intensity factor range as well as a strong dependency on the microstructural features such as grain boundaries, phase boundaries, and inclusions. To this end, a novel experimental framewo k is developed to investigate the sh rt fatigue crack behaviour of hydrogen charg materials involving in-situ observation of p opagating short cracks coupled with image processing to obtain their da/dN vs curves. Vari us metallic materials ranging from austenitic st in e s steel (AISI 316L) to reactor pressure vessel teel (SA508 Grade 3 Class I low alloy steel) and lin pipe steels (API 5L X65 & X80) re studied in this work. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers. ECF22 - Loading and Environmental effects on Structural Integrity Tracking hydrogen embrittlement using short fatigue crack behavior of metals Vishal Singh, Rajwinder Singh, Amanjot Singh, Dhiraj K. Mahajan* Ropar Mechanics of Materials Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Ropar, Rupnagar, Punjab, India, 140001 Abstract Understanding hydrogen embrittlement phenomenon that leads to deterioration of mechanical properties of metallic components is vital for pplications involving hydrogen environment. Among these, understanding the influence of hydrogen on the fatigue behaviour of metals is of great interest. Total fatigu life f a material can b divided into fati ue crack i itiation and fatigue crack rowt phase. Whil fatigue crack itiation can be link d with the propagation of short fatigue cracks, the size of which is of the order f grain size (few tens of microns), th are ge era ly not detec able by conve tional crack det tion tec niqu s applicable f r t long fati ue crack gro h behaviour u ing convention l CT specimens. Extensi literature is available on hydrog n effe t on long fatigue crack growth behaviour of metals that leads to the change in crack growth rate and th threshold stress intensity factor range ( ∆ �� ). Howeve , it is the short fatigu crack growth be aviour that provides the fundamen al und rstanding and correlation of the metallic microstructure with ydrogen mbrittlemen ph nomenon. Sho t fatigue crack growth behaviour is char cteristically different from long crack growth behaviour showing high pro agation rate at much lowe values t an threshold stress intensity factor range as well s a strong d pendency n the microstructural fe tures such as grain boundaries, phase boundar es, and in lusions. To this end, a n vel ex rimental fram work is developed to investigate the short fatigue crack behaviour of hydrogen charged materials involving i -situ obs vation o propagating short cracks coupled with image processing t obtain their da/dN vs curves. Various metallic materials ranging from austenitic stainless steel (AISI 316L) to re ctor pres ure vessel steel (SA508 Grad 3 Cla s I low alloy steel) and line pip steels (API 5L X65 & X80) ar studied in this w k. © 2018 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ECF22 organizers.

© 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. Keywords: Hydrogen embrittlement, short crack, fatigue, 316L, SA 508, X65, X80 Keywords: Hydrogen embrittlement, short crack, fatigue, 316L, SA 508, X65, X80

Keywords: High Pressure Turbine Blade; Creep; Finite Element Method; 3D Model; Simulation.

* Corresponding author. Tel.: +91-7814252244 E-mail address: dhiraj.mahajan@iitrpr.ac.in * Corresponding author. Tel.: +91-7814252244 E-mail ad ress: dhiraj.mahajan@iitrpr.ac.in

* 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 organizers.

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.2018.12.296