PSI - Issue 52

ScienceDirect Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2022) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2022) 000 – 000 Available online at www.sciencedirect.com

www.elsevier.com/locate/procedia

www.elsevier.com/locate/procedia

Procedia Structural Integrity 52 (2024) 89–98

© 2023 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) Peer-review under responsibility of Professor Ferri Aliabadi Abstract The present study was initiated to perform a detailed evaluation of the creep behaviour of a cast GTD 111 nickel-based superalloy. Over the past two decades, experimental studies have been carried out to investigate the creep mechanisms and microstructure changes in this superalloy at testing temperature frequently above 1000°C. However, the creep behaviour at intermediated temperatures has received only a very limited attention, especially for the creep testing temperatures around 900°C, which represent a transition situation between medium-temperatures and high-temperatures. Accordingly, the present work was undertaken to examine the flow characteristics and creep damage evolution in a cast GTD 111 nickel-based superalloy. Constant load creep tests were conducted at 800, 900 and 950°C under tensile stress range from 125 to 700 MPa. Creep tests were followed by metallographic and fractographic investigations using scanning and transmission electron microscopy. The study aims to identify operating creep deformation and damage mechanisms and to clarify the decisive factors governing the creep resistance of the superalloy under investigation. Fracture, Damage and Structural Health Monitoring Evaluation of High-Temperature Creep Behaviour in Cast GTD 111 Nickel-Based Superalloy Marie Kvapilova a, *, Petr Kral a , Jiri Dvorak a , Pavel Hutar a , Vaclav Sklenicka a a Institute of Physics of Materials, Czech Academy of Sciences, Zizkova 513/22, Brno616 62, Czech Republic Abstract The present study was initiated to perform a detailed evaluation of the creep behaviour of a cast GTD 111 nickel-based superalloy. Over the past two decades, experimental studies have been carried out to investigate the creep mechanisms and microstructure changes in this superalloy at testing temperature frequently above 1000°C. However, the creep behaviour at intermediated temperatures has received only a very limited attention, especially for the creep testing temperatures around 900°C, which represent a transition situation between medium-temperatures and high-temperatures. Accordingly, the present work was undertaken to examine the flow characteristics and creep damage evolution in a cast GTD 111 nickel-based superalloy. Constant load creep tests were conducted at 800, 900 and 950°C under tensile stress range from 125 to 700 MPa. Creep tests were followed by metallographic and fractographic investigations using scanning and transmission electron microscopy. The study aims to identify operating creep deformation and damage mechanisms and to clarify the decisive factors governing the creep resistance of the superalloy under investigation. Keywors: creep; nickel-based superalloy; creep deformation and fracture mechanisms; creep life 1. Introduction The blade material GTD 111 is a precipitation-strengthened nickel-based superalloy, which is employed mostly in gas turbines because of its high temperature strength and oxidation resistance. The GTD 111 superalloy was developed by the General Electric company and employed in the 1980s as a substitute for the former nickel-based superalloy IN738LC. During service, the GTD 111 superalloy is exposed to creep loading and thereby accentuates Fracture, Damage and Structural Health Monitoring Evaluation of High-Temperature Creep Behaviour in Cast GTD 111 Nickel-Based Superalloy Marie Kvapilova a, *, Petr Kral a , Jiri Dvorak a , Pavel Hutar a , Vaclav Sklenicka a a Institute of Physics of Materials, Czech Academy of Sciences, Zizkova 513/22, Brno616 62, Czech Republic Keywors: creep; nickel-based superalloy; creep deformation and fracture mechanisms; creep life 1. Introduction The blade material GTD 111 is a precipitation-strengthened nickel-based superalloy, which is employed mostly in gas turbines because of its high temperature strength and oxidation resistance. The GTD 111 superalloy was developed by the General Electric company and employed in the 1980s as a substitute for the former nickel-based superalloy IN738LC. During service, the GTD 111 superalloy is exposed to creep loading and thereby accentuates

* Corresponding author. Tel.: +420-532-290-374. E-mail address: kvapilova@ipm.cz * Corresponding author. Tel.: +420-532-290-374. E-mail address: kvapilova@ipm.cz

2452-3216 © 2023 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 ) Peer-review under responsibility of Professor Ferri Aliabadi 2452-3216 © 2023 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 ) Peer-review under responsibility of Professor Ferri Aliabadi

2452-3216 © 2023 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) Peer-review under responsibility of Professor Ferri Aliabadi 10.1016/j.prostr.2023.12.009