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Title: Coarsening behavior of {gamma}{double_prime} precipitates in modified Inconel 718 superalloy

Abstract

The growth of precipitate particles in precipitation-hardened alloys is very significant, because it can control the long-time mechanical properties of these alloys. The kinetics of this coarsening process have been accounted for in the theory of diffusion-controlled growth, based on the growth theory of Lifshitz and Slyozov and Wagner. The growth of {gamma}{prime} precipitate particles, which have an ordered fcc structure and precipitate coherently in many Ni-containing fcc alloys, follows the d {proportional_to} t{sup 1/3} law. Another commonly observed strengthening phase in many nickel alloys is {gamma}{double_prime}, which has a bct structure and precipitates coherently with a disk shape. A well-known example of this class of alloy, is the widely used commercial alloy, Inconel 718. Here, the measured coarsening kinetics of separate precipitation of {gamma}{double_prime} is found to be linearly related to the cube root of the aging time at 700 and 730 C. However, the coarsening behavior of {gamma}{double_prime} in a compact morphology of {gamma}{prime} + {gamma}{double_prime} in the modified alloy is different from that of Inconel 718. Initially the coarsening rate is very slow, but eventually it coarsens rapidly. The actual {gamma}{double_prime} particle size distribution of the modified alloy is skewed towards large particle size and differs significantlymore » from the theoretically predicted distribution. TEM observations also confirm the preferential dissolution of {gamma}{double_prime} during coarsening, which could be attributed to the presence of an easy-diffusion path or lies to in a short-circuit diffusion.« less

Authors:
; ;  [1]
  1. Univ. of Science and Technology, Beijing (China). Dept. of Materials Science and Engineering
Publication Date:
OSTI Identifier:
136942
Resource Type:
Journal Article
Journal Name:
Scripta Metallurgica et Materialia
Additional Journal Information:
Journal Volume: 33; Journal Issue: 12; Other Information: PBD: 15 Dec 1995
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; INCONEL 718; MICROSTRUCTURE; EXPERIMENTAL DATA; ALUMINIUM; TITANIUM; NIOBIUM; CHEMICAL COMPOSITION; TIME DEPENDENCE; GRAIN SIZE; TRANSMISSION ELECTRON MICROSCOPY

Citation Formats

Jianxin, Dong, Xishan, Xie, and Shouhua, Zhang. Coarsening behavior of {gamma}{double_prime} precipitates in modified Inconel 718 superalloy. United States: N. p., 1995. Web. doi:10.1016/0956-716X(95)00446-3.
Jianxin, Dong, Xishan, Xie, & Shouhua, Zhang. Coarsening behavior of {gamma}{double_prime} precipitates in modified Inconel 718 superalloy. United States. https://doi.org/10.1016/0956-716X(95)00446-3
Jianxin, Dong, Xishan, Xie, and Shouhua, Zhang. 1995. "Coarsening behavior of {gamma}{double_prime} precipitates in modified Inconel 718 superalloy". United States. https://doi.org/10.1016/0956-716X(95)00446-3.
@article{osti_136942,
title = {Coarsening behavior of {gamma}{double_prime} precipitates in modified Inconel 718 superalloy},
author = {Jianxin, Dong and Xishan, Xie and Shouhua, Zhang},
abstractNote = {The growth of precipitate particles in precipitation-hardened alloys is very significant, because it can control the long-time mechanical properties of these alloys. The kinetics of this coarsening process have been accounted for in the theory of diffusion-controlled growth, based on the growth theory of Lifshitz and Slyozov and Wagner. The growth of {gamma}{prime} precipitate particles, which have an ordered fcc structure and precipitate coherently in many Ni-containing fcc alloys, follows the d {proportional_to} t{sup 1/3} law. Another commonly observed strengthening phase in many nickel alloys is {gamma}{double_prime}, which has a bct structure and precipitates coherently with a disk shape. A well-known example of this class of alloy, is the widely used commercial alloy, Inconel 718. Here, the measured coarsening kinetics of separate precipitation of {gamma}{double_prime} is found to be linearly related to the cube root of the aging time at 700 and 730 C. However, the coarsening behavior of {gamma}{double_prime} in a compact morphology of {gamma}{prime} + {gamma}{double_prime} in the modified alloy is different from that of Inconel 718. Initially the coarsening rate is very slow, but eventually it coarsens rapidly. The actual {gamma}{double_prime} particle size distribution of the modified alloy is skewed towards large particle size and differs significantly from the theoretically predicted distribution. TEM observations also confirm the preferential dissolution of {gamma}{double_prime} during coarsening, which could be attributed to the presence of an easy-diffusion path or lies to in a short-circuit diffusion.},
doi = {10.1016/0956-716X(95)00446-3},
url = {https://www.osti.gov/biblio/136942}, journal = {Scripta Metallurgica et Materialia},
number = 12,
volume = 33,
place = {United States},
year = {1995},
month = {12}
}