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Title: Reasons for superior mechanical and corrosion properties of 2219 aluminum alloy electron beam welds

Abstract

Electron beam welds of aluminum alloy 2219 offer much higher strength compared to gas tungsten arc welds of the same alloy and the reasons for this have not been fully explored. In this study both types of welds were made and mechanical properties were evaluated by tensile testing and pitting corrosion resistance by potentio dynamic polarization tests. It is shown that electron beam welds exhibit superior mechanical and corrosion properties. The weld metals have been characterized by scanning electron microscopy; transmission electron microscopy and electron probe micro analysis. Presence of partially disintegrated precipitates in the weld metal, finer micro porosity and uniform distribution of copper in the matrix were found to be the reasons for superior properties of electron beam welds apart from the fine equiaxed grain structure. Transmission electron micrographs of the heat affected zones revealed the precipitate disintegration and over aging in gas tungsten arc welds.

Authors:
 [1];  [2];  [3];  [3];  [3]
  1. Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Madras, Chennai-600 036 (India). E-mail: sajjarkr@yahoo.com
  2. Defense Metallurgical Research Laboratory, Hyderabad-500 058 (India)
  3. Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Madras, Chennai-600 036 (India)
Publication Date:
OSTI Identifier:
20833174
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Characterization; Journal Volume: 55; Journal Issue: 4-5; Other Information: DOI: 10.1016/j.matchar.2005.07.006; PII: S1044-5803(05)00171-3; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM ALLOYS; COPPER; ELECTRON BEAM WELDING; ELECTRON BEAMS; ELECTRON MICROPROBE ANALYSIS; GAS TUNGSTEN-ARC WELDING; MECHANICAL PROPERTIES; PITTING CORROSION; POROSITY; SCANNING ELECTRON MICROSCOPY; TRANSMISSION ELECTRON MICROSCOPY; TUNGSTEN

Citation Formats

Koteswara Rao, S.R., Madhusudhan Reddy, G., Srinivasa Rao, K., Kamaraj, M., and Prasad Rao, K. Reasons for superior mechanical and corrosion properties of 2219 aluminum alloy electron beam welds. United States: N. p., 2005. Web. doi:10.1016/j.matchar.2005.07.006.
Koteswara Rao, S.R., Madhusudhan Reddy, G., Srinivasa Rao, K., Kamaraj, M., & Prasad Rao, K. Reasons for superior mechanical and corrosion properties of 2219 aluminum alloy electron beam welds. United States. doi:10.1016/j.matchar.2005.07.006.
Koteswara Rao, S.R., Madhusudhan Reddy, G., Srinivasa Rao, K., Kamaraj, M., and Prasad Rao, K. Tue . "Reasons for superior mechanical and corrosion properties of 2219 aluminum alloy electron beam welds". United States. doi:10.1016/j.matchar.2005.07.006.
@article{osti_20833174,
title = {Reasons for superior mechanical and corrosion properties of 2219 aluminum alloy electron beam welds},
author = {Koteswara Rao, S.R. and Madhusudhan Reddy, G. and Srinivasa Rao, K. and Kamaraj, M. and Prasad Rao, K.},
abstractNote = {Electron beam welds of aluminum alloy 2219 offer much higher strength compared to gas tungsten arc welds of the same alloy and the reasons for this have not been fully explored. In this study both types of welds were made and mechanical properties were evaluated by tensile testing and pitting corrosion resistance by potentio dynamic polarization tests. It is shown that electron beam welds exhibit superior mechanical and corrosion properties. The weld metals have been characterized by scanning electron microscopy; transmission electron microscopy and electron probe micro analysis. Presence of partially disintegrated precipitates in the weld metal, finer micro porosity and uniform distribution of copper in the matrix were found to be the reasons for superior properties of electron beam welds apart from the fine equiaxed grain structure. Transmission electron micrographs of the heat affected zones revealed the precipitate disintegration and over aging in gas tungsten arc welds.},
doi = {10.1016/j.matchar.2005.07.006},
journal = {Materials Characterization},
number = 4-5,
volume = 55,
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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