Impact Factor:6.2
DOI number:10.1016/j.jallcom.2021.158865
Affiliation of Author(s):中南大学粉末冶金研究院， 烟台大学
Teaching and Research Group:高温结构材料研究所
Journal:Journal of Alloys and Compounds
Funded by:国家科技重大项目（2017-VI-0008-0078），中国国家自然科学基金（NSFC）（91860105，52074366），中国博士后科学基金会（2019M662799），中国山东主要科技创新项目（2019JZZY010325）
Key Words:Powder metallurgy superalloys, Fine grain, Creep, Dislocation, Critical stress
Abstract:In this work, the high temperature creep properties of three newly developed P/M superalloys with fine grains were investigated under conditions of 650 degrees C/1100 MPa, 750 degrees C/690 MPa, and 815 degrees C/550 MPa. The creep behavior associated with microstructure were analyzed, considering the interactions of dislocation with grain boundaries and gamma' phase. The results indicated that the cracks were more likely to initiate at grain boundaries, resulting in intergranular cracking. Moreover, the dislocation movement in grains was strongly related with testing temperature and applied stress, which is explained by theoretical calculation on the composition-dependent critical stresses (CSs) to trigger various mechanisms, including dislocation shearing the gamma' phase by stacking faults (SFs) or APB coupled dislocation pairs, and dislocation climbing. (C) 2021 Elsevier B.V. All rights reserved.
Co-author:Zexin Wang, Xiangyou Xiao, Yunping Li, Xia Li, Hua Zhang, Lilong Zhu, Liang Jiang, Yong Liu
First Author:Feng Liu
Indexed by:Article
Correspondence Author:Liming Tan, Xia Li
Document Code:158865
Discipline:Engineering
First-Level Discipline:冶金
Volume:867
ISSN No.:0925-8388
Translation or Not:no