Insight into element segregation mechanisms during creep in γ'-strengthened Co-based superalloy by elastoplastic phase-field simulation  

作　　者：Jia Chen Min Guo Min Yang Tingting Cui Borong Cui Jun Zhang 

机构地区：[1]State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi'an,710072,China

出　　处：《Progress in Natural Science:Materials International》2024年第5期873-879,共7页自然科学进展·国际材料(英文版)

基　　金：the supports provided by National Natural Science Foundation of China (51971174, 52031012,52301171);Research Fund of the State Key Laboratory of Solidification Processing,NPU)(2022-TZ-01);National Science and Technology Major Project (2017-VI-0001-0070);the Science and Technology Innovation Team Plan of Shaan Xi Province (2021TD-17)

摘　　要：The element segregation accompanying the creep process has been shown to significantly affect the deformation resistance of the superalloys. However, the processing and mechanism of element segregation are still unclear.This paper investigated the concentration evolution of a model Co–9Al–9W(at. %) alloy during 900℃/275 MPa using developed ternary elastoplastic phase-field model coupled with CALPHAD method and crystal plasticity model. The results of simulation show that co-depletion of Al and W element occurs in γ' precipitate and in γ side at γ/γ' interface, and this depletion is gradually increasing with the accumulation of plastic strain. From the perspective of changes of driving force of element diffusion, it is found that these segregation phenomena are attributed to the high elastic potential caused by the large local plastic strain. In addition, the effects of these segregations on creep property are also predicted. The current research provides a new method for exploring the mechanism of element diffusion.

关 键 词：Element segregation CREEP Phase-field simulation Co-based superalloys 

分 类 号：TG132.3[一般工业技术—材料科学与工程]