Mechanism of α-Cr precipitation and crystallographic relationships between α-Cr and δ phases in Inconel 718 alloy after long-time thermal exposure  

作　　者：Zhong-nan Bi Jian-xin Dong Mai-cang Zhang Lei Zheng Xi-shan Xie 

机构地区：[1]School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China

出　　处：《International Journal of Minerals,Metallurgy and Materials》2010年第3期312-317,共6页矿物冶金与材料学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No50771011)

摘　　要：To study the precipitation mechanism of α-Cr phase in Inconel 718 alloy, the samples after long-time aging at 650 and 677℃ were examined by microstructural observations and chemical phase analysis methods. Combining the thermodynamics and kinetics calculation results, α-Cr always precipitates in the vicinity of δ phase, because δ phase rejects Cr into the γ-matrix when growing. The selected area diffraction patterns confirm that the crystallographic relationships of α-Cr with 6 phase are （010）d/（1- 10）a.Cr and [100]d/If 11 ]α-Cr- A graphic model is also presented to show the crystallographic relation between α-Cr and δ phases.To study the precipitation mechanism of α-Cr phase in Inconel 718 alloy, the samples after long-time aging at 650 and 677℃ were examined by microstructural observations and chemical phase analysis methods. Combining the thermodynamics and kinetics calculation results, α-Cr always precipitates in the vicinity of δ phase, because δ phase rejects Cr into the γ-matrix when growing. The selected area diffraction patterns confirm that the crystallographic relationships of α-Cr with 6 phase are （010）d/（1- 10）a.Cr and [100]d/If 11 ]α-Cr- A graphic model is also presented to show the crystallographic relation between α-Cr and δ phases.

关 键 词：Inconel 718 precipitation mechanism CRYSTALLOGRAPHY THERMODYNAMICS kinetics 

分 类 号：TG146.15[一般工业技术—材料科学与工程] TQ153.2[金属学及工艺—金属材料]