Influence of y' precipitate-size and distribution on LCF behavior of a PM disk superalloy - Archive ouverte HAL Accéder directement au contenu
Communication Dans Un Congrès Année : 2012

Influence of y' precipitate-size and distribution on LCF behavior of a PM disk superalloy

(1) , (1) , (1) , (1) , (1) , (1) , (2)
1
2

Résumé

The influence of γ' precipitate distribution on tensile and low cycle fatigue (LCF) behaviors of a powder metallurgy (PM) disk superalloy was investigated at 450°C. Four γ' particle distributions were obtained through various cooling paths and/or aging treatments in coarse grain size superalloy N18. The mechanical tests show that the main influence of the intragranular microstructure concerns the 0.2% yield stress (0.2%YS) and the ultimate tensile stress. Wide variations of the 0.2%YS affect the mean stress under non symmetrical loading but have only little effect on fatigue life, the lower the 0.2%YS, the longer the fatigue life. The fatigue life of N18 at 450°C is independent of the intragranular microstructure as long as the mean stress effect is correctly taken into account. As expected with the coarse grain size N18, no crack initiation at pores or inclusions was observed. A precipitation model was coupled with a critical resolved shear stress calculation providing 0.2%YS value for a given heat treatment sequence. Finally, this computation procedure was implemented in a numerical modeling of the LCF life of a disk taking into account the heat treatment applied to its wrought preform.
Fichier principal
Vignette du fichier
Boittin-Locq-Cailletaud Superalloys 2012 167-176.pdf (5.37 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte
Loading...

Dates et versions

hal-00743347 , version 1 (21-02-2018)

Identifiants

  • HAL Id : hal-00743347 , version 1

Citer

Guylaine Boittin, D. Locq, A. Rafray, P. Caron, Pascale Kanoute, et al.. Influence of y' precipitate-size and distribution on LCF behavior of a PM disk superalloy. Superalloys 2012 ; 12th international symposium on superalloys, Sep 2012, Seven Springs, United States. pp.167-176. ⟨hal-00743347⟩
156 Consultations
160 Téléchargements

Partager

Gmail Facebook Twitter LinkedIn More