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Title: Effects of Li content on precipitation in Al-Cu-(Li)-Mg-Ag-Zr alloys

Abstract

Although much attention has been paid to Al-Cu-Li-Mg-Ag-Zr alloys, there are sparse reports about the influence of Li on precipitation in these alloys. The aim of the present study is to determine the effects of Li on modifying precipitation in a baseline aluminum alloy 2195 and the accompanying variants with 0--1.6 wt.% Li.

Authors:
;  [1]
  1. Central South Univ. of Technology, Changsha (China). Dept. of Materials Science and Engineering
Publication Date:
OSTI Identifier:
603857
Resource Type:
Journal Article
Resource Relation:
Journal Name: Scripta Materialia; Journal Volume: 38; Journal Issue: 3; Other Information: PBD: 6 Jan 1998
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM BASE ALLOYS; MICROSTRUCTURE; LITHIUM ADDITIONS; METALLURGICAL EFFECTS; COPPER ALLOYS; MAGNESIUM ADDITIONS; SILVER ADDITIONS; ZIRCONIUM ADDITIONS; PRECIPITATION

Citation Formats

Huang, B.P., and Zheng, Z.Q.. Effects of Li content on precipitation in Al-Cu-(Li)-Mg-Ag-Zr alloys. United States: N. p., 1998. Web. doi:10.1016/S1359-6462(97)00503-4.
Huang, B.P., & Zheng, Z.Q.. Effects of Li content on precipitation in Al-Cu-(Li)-Mg-Ag-Zr alloys. United States. doi:10.1016/S1359-6462(97)00503-4.
Huang, B.P., and Zheng, Z.Q.. 1998. "Effects of Li content on precipitation in Al-Cu-(Li)-Mg-Ag-Zr alloys". United States. doi:10.1016/S1359-6462(97)00503-4.
@article{osti_603857,
title = {Effects of Li content on precipitation in Al-Cu-(Li)-Mg-Ag-Zr alloys},
author = {Huang, B.P. and Zheng, Z.Q.},
abstractNote = {Although much attention has been paid to Al-Cu-Li-Mg-Ag-Zr alloys, there are sparse reports about the influence of Li on precipitation in these alloys. The aim of the present study is to determine the effects of Li on modifying precipitation in a baseline aluminum alloy 2195 and the accompanying variants with 0--1.6 wt.% Li.},
doi = {10.1016/S1359-6462(97)00503-4},
journal = {Scripta Materialia},
number = 3,
volume = 38,
place = {United States},
year = 1998,
month = 1
}
  • The morphology of discontinuous precipitation of the {sigma}{prime} phase is investigated in very high Li concentration Al-Li-Zr alloys using transmission electron microscopy. Contrary to previous observations, the reaction was found to initiate during quenching following solution heat treatment. Furthermore, the reaction was found to be very sensitive to the cooling rate from the solution treatment temperature since this could change the solute distribution in the vicinity of a grain boundary. It is demonstrated that the initiation of discontinuous precipitation in Al-Li alloys can not be explained in terms of recrystallization pressures that the grain boundaries are repelled by developing discontinuousmore » {sigma}{prime} colonies leading to gross distortion of the grain boundaries. The reaction mechanisms involved, and existing and new models for the discontinuous precipitation of {sigma}{prime}, are discussed in the light of these observations.« less
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