Accéder directement au contenu Accéder directement à la navigation
Article dans une revue

Relationships between Microstructural Parameters and Time-Dependent Mechanical Properties of a New Nickel-Based Superalloy AD730™

Abstract : High temperature creep and dwell-fatigue properties of the new nickel-based superalloy AD730™ have been investigated. Three microstructures have been studied in creep (850 °C and 700 °C) and dwell-fatigue (700 °C stress control with trapezoidal signals, and dwell times ranging from 1 s to 3600 s): a coarse grains microstructure, a fine grains one, and single crystalline samples. The aim of this study is to assess the influence of the grain size on creep and creep-fatigue properties. It is demonstrated that fine and coarse grains microstructures perform similarly in creep at 700 °C, showing that the creep properties at this temperature are controlled by the intragranular precipitation. Moreover, both the coarse grains and the fine grains microstructures show changes in creep deformation mechanisms depending on the applied stress in creep at 700 °C. At higher creep temperatures, the coarse grains microstructure performs better and almost no effect is observed by suppressing grain boundaries. During dwell-fatigue tests at 700 °C, a clear effect of the mechanical cycling has been evidenced on the time to failure on both the coarse and the fine grains microstructures. At high applied stresses, a beneficial effect of the cyclic unloading to the lifetime has been observed whereas at lower applied stresses, mechanical cycling is detrimental compared to the pure creep lifetime due to the development of a fatigue damage. Complex creep-fatigue interactions are hence clearly evidenced and they depend on the pure creep behavior reference.
Type de document :
Article dans une revue
Liste complète des métadonnées

https://hal-mines-paristech.archives-ouvertes.fr/hal-02902535
Contributeur : Magalie Prudon <>
Soumis le : lundi 20 juillet 2020 - 09:24:14
Dernière modification le : mercredi 4 novembre 2020 - 12:36:02

Lien texte intégral

Identifiants

Citation

Louis Thébaud, Patrick Villechaise, Jonathan Cormier, Coraline Crozet, Alexandre Devaux, et al.. Relationships between Microstructural Parameters and Time-Dependent Mechanical Properties of a New Nickel-Based Superalloy AD730™. Metals, MDPI, 2015, 5 (4), pp.2236-2251. ⟨10.3390/met5042236⟩. ⟨hal-02902535⟩

Partager

Métriques

Consultations de la notice

41