Microscopic phase-field simulation of L1_2 and D0_(22) phases during the early precipitation process of Ni-Cr-Al alloys  

作　　者：Zhong Chu Zheng Chen Yongxin Wang Yanli Lu Yongsheng Li 

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

出　　处：《Journal of University of Science and Technology Beijing》2006年第5期429-434,共6页北京科技大学学报（英文版）

基　　金：This work was financially supported by the National Natural Science Foundation of China (No.50071046) and the National High-Tech Research and Development Program of China (No.2002AA331051).

摘　　要：The influence of temperature on the precipitation mechanism and sequence of L 12 and D022 phases during the early precipitation process of a Ni-15.Sat%Cr-14at%Al alloy was simulated based on the microscopic phase-field model. In the range from 873 to 1373 K, the precipitation mechanism transformed from spinodal decomposition to non-classic nucleation and growth; the incubation period prolonged gradually with increasing temperature. The volume fraction of L12 phases increased and that of D022 phases decreased. D022 phases disappeared at 1373 K, and finally single-phase L12 phases were formed.The influence of temperature on the precipitation mechanism and sequence of L 12 and D022 phases during the early precipitation process of a Ni-15.Sat%Cr-14at%Al alloy was simulated based on the microscopic phase-field model. In the range from 873 to 1373 K, the precipitation mechanism transformed from spinodal decomposition to non-classic nucleation and growth; the incubation period prolonged gradually with increasing temperature. The volume fraction of L12 phases increased and that of D022 phases decreased. D022 phases disappeared at 1373 K, and finally single-phase L12 phases were formed.

关 键 词：Ni-Cr-AI alloys microscope phase-field model precipitation ordering parameter simulation 

分 类 号：TG146.15[一般工业技术—材料科学与工程]