PSI - Issue 14

ScienceDirect Available online at www.sciencedirect.com Av ilable online at www.sciencedire t.com cienceDirect Structural Integrity Procedia 00 (2016) 000 – 000 Procedia Structu al Integrity 14 (2019) 7 5–711 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 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 ienc Direct

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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. © 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. 2nd International Conference on Structural Integrity and Exhibition 2018 Effect of Cold Working on Corrosion Fatigue Behavior of Austenitic Stainless Steel in Acidified Chloride medium A. Poonguzhali a,b,* , S. Ningshen a,b and G.Amarendra a,b a Corrosion Science and Technology Division, IGCAR, Kalpakkam – 603 102, India b Homi Baba National Institute, IGCAR, Kalpakkam Abstract Nitrogen is one of the most important alloying elements in alloy steels and even in small amounts can improve their prop rties. Becaus of its favorable properties, high performance nitrogen containing austenitic stainless steels are currently being developed for an advanced application that requires high strength along with better corrosion and wear resistance. The present study investigate the effects of cold work (CW) on the microstructure and corrosion fatigue (CF) resistance of AISI Type 316 LN stainless steel containing 0.11 wt. % nitrogen using microscopic, electrochemical and surface analytical methods. Potentiodynamic anodic polarization experiments were carried out in two chloride concentrations (1 M NaCl) and (5 M NaCl + 0.15 M Na 2 SO 4 ) indicated that pitting potential (E pit ) and passivity range drastically decreased with increase in chloride concentration and increased deformation from 0 to 20% CW. In 5 M NaCl + 0.15 M Na 2 SO 4 , corrosion resistance (R p ) decreases with an increase in cold work due to increased susceptibility of the passive film towards dissolution due to increase in dislocation density. CF behaviour of AISI Type 316LN SS with 0.11 wt.% nitrogen was studied in acidified 5 M NaCl + 0.15M Na 2 SO 4 solution at a stress ratio (R) of 0.5 and a frequency (η) of 0.1 Hz with varying mean stress (σ mean ) and open circuit potential was monitored throughout till the failure of the specimen occur. Based on in-situ electrochemical measurements during corrosion fatigue tests, the shift in potential indicates the crack initiation process. The S-N curve of fatigue life (Nf) vs. stress amplitude was also generated. This study showed that the CF resistance increases with an increase in cold work and the number of cycles to failure and critical cracking potential decreases with increasing mean stress. The crack initiation and propagation show a transgranular mode in all the tested conditions. K ywords: Corrosion fatigue; itrogen; pitting; stainless steel; SEM 2nd International Conference on Structural Integrity and Exhibition 2018 Effect of Cold Working on Corros on Fatigue Behavior of Austenitic Stainless Steel in Acidified Chloride medium A. Poonguzhali a,b,* , S. Ningshen a,b and G.Amarendra a,b a Corrosion Science and Technology Division, IGCAR, Kalpakkam – 603 102, India b Homi Baba National Institute, IGCAR, Kalpakkam Abstract Nitrogen is one of the most important alloying elements in alloy steels and even in small amounts can improve their properties. Because of its favorable properties, high performance nitrogen containing austenitic stainless steels are currently being developed for an advanced application that requires high strength along with better corrosion and wear resistance. The present study investigate the effects of cold work (CW) on the microstructure and corrosion fatigue (CF) resistance of AISI Type 316 LN stainless steel containing 0.11 wt. % nitrogen using microscopic, electrochemical and surface analytical methods. Potentiodynamic anodic polarization experi ents were carried out in two chloride concentrations (1 M NaCl) and (5 M NaCl + 0.15 M Na 2 SO 4 ) indicated that pitting potential (E pit ) and passivity range drastically decreased with increase in chloride concentration and increased deformation from 0 to 20% CW. In 5 M NaCl + 0.15 M Na 2 SO 4 , corrosion resistance (R p ) decreases with an increase in cold work due to increased susceptibility of the passive film towards dissolution due to increase in dislocation density. CF behaviour of AISI Type 316LN SS with 0.11 wt.% nitrogen was studied in acidified 5 M NaCl + 0.15M Na 2 SO 4 solution at a stress ratio (R) of 0.5 and a frequency (η) of 0.1 Hz with varying mean stress (σ mean ) and open circuit potential was monitored throughout till the failure of the speci en occur. Based on in-situ electrochemical measurements during corrosion fatigue tests, the shift in potential indicates the crack initiation process. The S-N curve of fatigue life (Nf) vs. stress amplitude was also generat d. This study sh wed that the CF resistance incr ases with an increase in cold work and the number of cycles to f ilure nd critical cracking potential decreases with increasing mean stress. The crack init ation and propagation show a tran granular mode in all the tested conditions. 2nd International Conference on Structural Integrity and Exhibition 2018 Effect of Cold Working on Corrosion Fatigue Behavior of Austenitic Stainless Steel in Acidified Chloride medium A. Poonguzhali a,b,* , S. Ningshen a,b and G.Amarendra a,b a Corrosion Science and Technology Division, IGCAR, Kalpakkam – 603 102, India b Homi Baba National Institute, IGCAR, Kalpakkam Abstract Nitrogen is one of the most important alloying elements in alloy steels and even in small amounts can improve their properties. Because of its favorable properties, high performance itrogen containing austenitic stainless steels are currently being develop d for an advanced pplicatio that requires high trength along with better c rro ion and wear res stance. The present study investig te the effects of cold work (CW) on th microstructure and corrosion fatigu (CF) resistance of AISI Type 316 LN stainless steel containing 0.11 wt. % nitrogen using microscopic, electrochemical and surface analytical m thods. Potentiodynamic anodic p larization experiments w re ca ried out in two hloride concentrations (1 M NaCl) and (5 M NaCl + 0.15 M Na 2 SO 4 ) indicated that pitting p tential (E pit ) and passivity range drastic lly decreased wi h incr ase in chloride co centr ti n and increased defor ation from 0 to 20% CW. In 5 M NaCl + 0.15 M Na 2 SO 4 , corrosion resistance (R p ) decreases with an increase in cold work due to increased susce tibility of the passive film towards issolution du to incre se in disloc tion density. CF behaviour of AISI Type 316LN SS with 0.11 wt.% nitrogen w s studied in acidified 5 M NaCl + 0.15M Na 2 SO 4 solution at a stres ratio (R) of 0.5 a a frequenc (η) of 0.1 Hz with varying mean stress (σ mean ) and op n circuit potential was monitored throughout till the failure of the specimen occur. Bas d on in-situ electrochemical measurements during corrosion fatigue test , the shift in pote tial indicates the crack initiation process. The S-N curve of f tigue life (Nf) vs. stress amplitude was also generated. This study showed that the CF resistance i crea es with an increase in cold work and the number of cycles to failure and critical cracki g potential de reases with increasing mean stress. The crack initiation and propagation show a transgranular mode in all the tested conditions. Keywords: Corrosi n fatigue; nit ogen; pitting; st i less steel; SEM Austenitic stainless steels are chosen as the most common multi-component constructions materials used in the nuclear industry due to the combination of good high temperature mechanical properties, compatibility with coolant liquid sodium, good weldability, and resistance to intergranular stress corrosion cracking (IGSCC) by reducing the carbon content. As, an alloyi g element, nitrogen in combination with molybdenum improves resistance to localized corrosion due t self-healing and protective passive film. The pitting corrosion resist nce is significantly affect d by met llurgical parameters like cold working, all y 2nd International Conference on Structural Integrity and Exhibition 2018 Effect of Cold Working on Corrosion Fatigue Behavior of Austenitic Stai less Steel in Acidified Chloride medium A. Poonguzhali a,b,* , S. Ningshen a,b and G.Amarendra a,b a Corrosion Science and Technology Division, IGCAR, Kalpakkam – 603 102, India b Homi Baba National Inst tute, IGCAR, Kalpa kam Abstract Nitrogen is on the most important alloyin elements i alloy ste ls and eve in small amounts can improv their properties. Becaus its favorable pro erties, hig performance nitrog n containing aust nitic stainless steels ar currently being d v loped for an advanced application that requires high strength along with better corrosion and wear . The present study inve igat the ffects of cold work (CW) on the microstructure and corr si n fatigue (CF) r sist of AISI Type 316 LN stainl ss steel containing 0.11 wt. % nitrogen using microscopic, electrochemical and surface analytical methods. Potentiody amic anodic polar z ion experiments were carried out in two chloride concentratio s (1 M NaCl) and (5 M NaCl + 0.15 M Na 2 SO 4 ) indic ted that pitting potential (E pit ) and passivity range drastically decreased with inc ease i chloride concentration and incr ased deformation from 0 to 20% CW. In 5 M NaCl + 0.15 M Na 2 SO 4 , corrosion resistanc (R p ) decreas s with an i crease in cold work due to increased susceptibility of the passive film towards dissolution due to increase in dislocation de sity. CF behaviour of AISI Type 316LN SS with 0.11 wt.% nitrogen was studied in acidified 5 M NaCl + 0.15M Na 2 SO 4 solution a a stress ratio R) of 0.5 and a frequency (η) of 0.1 Hz with varying mean stress (σ mean ) and op n circuit potential was mon tored throughout till the failure of the specimen occur. Based on in-situ electrochemical measurements during corrosion fatigue te ts, the shift in potential indicates the crack in ti tion process. The S-N curv of fatigue life (Nf) vs. stress amplitude wa also gen r te . Th s study showed that the CF resi tance es with an increase in cold work and the number of cycles to failure and critical cracking potential decreases with i r sing mean stress. The crack initiation and propagation show a transgranular mode in all the tested conditions. Keywords: Corrosion fatigue; nitrogen; pitting; stainless steel; SEM 1. Introduction Auste itic sta nless steels are c osen as the most common multi-component constructions mater als used in the nuclear industry ue to the c mbination of good h gh temperature mechanical pr pert es, ompatibility with coolant l quid sodium, good weldability, and resistanc to int r ranular stress c rrosion cracking (IGSCC) by reducing the carbon ntent. As, an all ying element, nit og n in combinat on with molybdenum mproves resistance t localized corrosion due to self-healing and protective passive film. The pitting corrosion resistance is significantly affected by metallurgical parameters like cold working, alloy f Cold Working on Corros on Fatigue Behavior of c i d ori ediu A s r c di a t i cu t n i r se i 1 c c c m © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. 1. Introduction Keywords: Corrosion fatigue; nitrogen; pitting; stainless steel; SEM Keywords: High Pressure Turbine Blade; Creep; Finite Element Method; 3D Model; Simulation. Austenitic stainless steels are chosen as the most common multi-component constructions materials used in the nuclear industry due to the combination of good high temperature mechanical properties, compatibility with coolant liquid sodium, good weldability, and resistance to intergranular stress corrosion cracking (IGSCC) by reducing the carbon content. As, an alloying element, nitrogen in combination with molybdenum improves resistance to localized corrosion due to self-healing and protective passive film. The pitting corrosion resistance is significantly affected by metallurgical parameters like cold working, alloy Austenitic stainless steels are chosen as the most common multi-component constructions materials used in the nuclear industry due to the combination of good high temperature mechanical properties, compatibility with coolant liquid sodium, good weldability, and resistance to intergranular stress corrosion cracking (IGSCC) by reducing the carbon content. As, an alloying element, nitrogen in combination with molybdenum improves resistance to localized corrosion due to self-healing and protective passive film. The pitting corrosion resistance is significantly affected by metallurgical parameters like cold working, alloy 1. Introduction 1. Introduction

* Corresponding author. Tel.: +351 218419991. E-mail address: amd@tecnico.ulisboa.pt * Corresponding author. E-mail address: apoongs@igcar.gov.in * Corresponding author. E-mail address: apoongs@igcar.gov.in * Corresponding author. E-mail address: apoongs@igcar.gov.in

2452-3216 © 2016 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of PCF 2016. 2452-3216  2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. 10.1016/j.prostr.2019.05.088 2452-3216 © 2018 The Authors. Published by Elsevier B.V. This is an open ccess article under the CC BY-NC-ND license (h tps://creativecommon .org/licenses/by-nc-nd/4.0/) Selection and peer-review under re ponsibility of P er-review under responsibility of the SICE 2018 organizers. 2452-3216 © 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review under responsibility of Peer-review under responsibility of the SICE 2018 organizers. * Corresponding author. E-mail address: apoongs@igcar.gov.in 2452-3216 © 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review under responsibi ity of Peer-review under responsibility of the SICE 2018 organizers. 2452-3216 © 2018 The Authors. Published by Elsevier B.V. This is a open access article under the CC BY-NC-ND lic nse (https://creativecommons.org/licenses/by- c-nd/4.0/) Selection and peer-review under responsibility of Peer-revi w under responsibility of the SICE 2018 orga izers.