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Title: High current pulsed electron beam treatment of AZ31 Mg alloy

Abstract

This paper reports, for the first time, an analysis of the effect of High Current Pulsed Electron Beam (HCPEB) on a Mg alloy. The AZ31 alloy was HCPEB treated in order to see the potential of this fairly recent technique in modifying its wear resistance. For the 2.5 J/cm{sup 2} beam energy density used in the present work, the evaporation mode was operative and led to the formation of a ''wavy'' surface and the absence of eruptive microcraters. The selective evaporation of Mg over Al led to an Al-rich melted surface layer and precipitation hardening from the over saturated solid solution. Due to the increase in hardness of the top surface layer, the friction coefficient values were lowered by more than 20% after the HCPEB treatments, and the wear resistance was drastically (by a factor of 6) improved. The microhardness of the HCPEB samples was also increased significantly down to a depth of about 500 {mu}m, far exceeding the heat-affected zone (about 40 {mu}m). This is due to the effect of the propagation of the shockwave associated with this HCPEB treatment.

Authors:
; ; ; ; ; ;  [1];  [2];  [3]
  1. State Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams and Department of Materials Engineering, Dalian University of Technology, Dalian 116024 (China)
  2. (LETAM, UMR-CNRS 7078), Universite de Metz, Ile du Saulcy, 57 012 Metz (France)
  3. (China)
Publication Date:
OSTI Identifier:
20723202
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 23; Journal Issue: 6; Other Information: DOI: 10.1116/1.2049299; (c) 2005 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ELECTRON BEAMS; ENERGY DENSITY; EVAPORATION; FRICTION; HEAT AFFECTED ZONE; LAYERS; MAGNESIUM ALLOYS; MANGANESE ALLOYS; MICROHARDNESS; PRECIPITATION HARDENING; SOLID SOLUTIONS; WEAR RESISTANCE; ZINC ALLOYS

Citation Formats

Gao Bo, Hao Shengzhi, Zou Jianxin, Grosdidier, Thierry, Jiang Limin, Zhou Jiyang, Dong Chuang, Laboratoire d'Etude des Textures et Applications aux Materiaux, and State Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams and Department of Materials Engineering, Dalian University of Technology, Dalian 116024. High current pulsed electron beam treatment of AZ31 Mg alloy. United States: N. p., 2005. Web. doi:10.1116/1.2049299.
Gao Bo, Hao Shengzhi, Zou Jianxin, Grosdidier, Thierry, Jiang Limin, Zhou Jiyang, Dong Chuang, Laboratoire d'Etude des Textures et Applications aux Materiaux, & State Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams and Department of Materials Engineering, Dalian University of Technology, Dalian 116024. High current pulsed electron beam treatment of AZ31 Mg alloy. United States. doi:10.1116/1.2049299.
Gao Bo, Hao Shengzhi, Zou Jianxin, Grosdidier, Thierry, Jiang Limin, Zhou Jiyang, Dong Chuang, Laboratoire d'Etude des Textures et Applications aux Materiaux, and State Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams and Department of Materials Engineering, Dalian University of Technology, Dalian 116024. Tue . "High current pulsed electron beam treatment of AZ31 Mg alloy". United States. doi:10.1116/1.2049299.
@article{osti_20723202,
title = {High current pulsed electron beam treatment of AZ31 Mg alloy},
author = {Gao Bo and Hao Shengzhi and Zou Jianxin and Grosdidier, Thierry and Jiang Limin and Zhou Jiyang and Dong Chuang and Laboratoire d'Etude des Textures et Applications aux Materiaux and State Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams and Department of Materials Engineering, Dalian University of Technology, Dalian 116024},
abstractNote = {This paper reports, for the first time, an analysis of the effect of High Current Pulsed Electron Beam (HCPEB) on a Mg alloy. The AZ31 alloy was HCPEB treated in order to see the potential of this fairly recent technique in modifying its wear resistance. For the 2.5 J/cm{sup 2} beam energy density used in the present work, the evaporation mode was operative and led to the formation of a ''wavy'' surface and the absence of eruptive microcraters. The selective evaporation of Mg over Al led to an Al-rich melted surface layer and precipitation hardening from the over saturated solid solution. Due to the increase in hardness of the top surface layer, the friction coefficient values were lowered by more than 20% after the HCPEB treatments, and the wear resistance was drastically (by a factor of 6) improved. The microhardness of the HCPEB samples was also increased significantly down to a depth of about 500 {mu}m, far exceeding the heat-affected zone (about 40 {mu}m). This is due to the effect of the propagation of the shockwave associated with this HCPEB treatment.},
doi = {10.1116/1.2049299},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 6,
volume = 23,
place = {United States},
year = {Tue Nov 15 00:00:00 EST 2005},
month = {Tue Nov 15 00:00:00 EST 2005}
}
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