Creep-rupture behavior of a nickel-based single crystal superalloy

5th International Symposium on Hydrogen Energy, Renewable Energy and Materials

能源学;材料科学

Liu, Weiwei^1 ; Guo, Yuanyuan^1 ; Zhang, Mai^1^2 ; Xiong, Jichun^1 ; Zhang, Jian^1

Science and Technology on Advanced High Temperature Structural Materials Laboratory, Beijing Institute of Aeronautical Materials, Beijing

100095, China^1

School of Materials Science and Engineering, University of Science and Technology, Beijing

100083, China^2

关键词: Creep behaviors;    Creep rates;    Creep ruptures;    High temperature creep;    Interfacial dislocations;    Low angle boundaries;    Single crystal superalloys;    Steady creeps;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/605/1/012021/pdf
DOI  :  10.1088/1757-899X/605/1/012021

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

A first generation single crystal superalloy was employed to research the high temperature creep behavior. Scanning electron microscope (SEM), transmission electron microscope (TEM) are used. The main results are summarized below: There are two mechanisms for the steady creep. The first one is superlattice dislocation cutting γ′ precipitates, which is the main mechanism for 1000°C creep behavior. In this case, the creep rate increases when the γ/γ′ microstructure undergoes topological inversion, which leads to a rapid increase in the density of γ′ cutting dislocation. The second mechanism is transverse climb of a/2 interfacial dislocation, which is the main mechanism for 1100°C creep behavior. In this case, climb of interfacial dislocations produced most of the steady creep strain. A by-product is the vacancies diffusing along the interfaces and low angle boundary to pores.