Grain boundary development in superplastic aluminum alloys
Approved for public release; distribution is unlimited === Superplasticity may be defined as the capability of certain polycrystalline materials to deform to extensive plastic elongations prior to failure, often without formation of a neck. Typically, superplasticity refers to tensile elongations gr...
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Monterey, California. Naval Postgraduate School
2012
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ndltd-nps.edu-oai-calhoun.nps.edu-10945-84522015-06-20T16:02:33Z Grain boundary development in superplastic aluminum alloys McMahon, Michael Edward McNelley, T.R. Mechanical Engineering Approved for public release; distribution is unlimited Superplasticity may be defined as the capability of certain polycrystalline materials to deform to extensive plastic elongations prior to failure, often without formation of a neck. Typically, superplasticity refers to tensile elongations greater than 200%, although some elongations have been reported in excess of 5000% Ref 1. While it has been suggested that bronze metals in use in ancient civilizations may have possessed superplastic properties Ref 2, most historical reviews credit the modern-day documentation of superplastic behavior to a paper published in the Journal of the Institute of Metals by G.D. Bengough in 1912 which described extensive elongations in brass Ref 3. Recognition of a stress and strain-rate relationship was first presented qualitatively in a paper by Rosenhain in 1920 which examined a near eutectic Zn- Al-Cu alloy Ref 4. Photomicrographs detailing superplastic grain structures in eutectic Sn-Pb and Bi-Pb alloys deformed to elongations of 2000% were presented in 1934 by Pearson Ref 5. This study was the first to identify an equiaxed grain morphology in the deformed regions and suggest that grain boundary migration may be involved in the deformation processes 2012-08-09T19:20:54Z 2012-08-09T19:20:54Z 1996-12 Thesis http://hdl.handle.net/10945/8452 en_US Monterey, California. Naval Postgraduate School |
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Approved for public release; distribution is unlimited === Superplasticity may be defined as the capability of certain polycrystalline materials to deform to extensive plastic elongations prior to failure, often without formation of a neck. Typically, superplasticity refers to tensile elongations greater than 200%, although some elongations have been reported in excess of 5000% Ref 1. While it has been suggested that bronze metals in use in ancient civilizations may have possessed superplastic properties Ref 2, most historical reviews credit the modern-day documentation of superplastic behavior to a paper published in the Journal of the Institute of Metals by G.D. Bengough in 1912 which described extensive elongations in brass Ref 3. Recognition of a stress and strain-rate relationship was first presented qualitatively in a paper by Rosenhain in 1920 which examined a near eutectic Zn- Al-Cu alloy Ref 4. Photomicrographs detailing superplastic grain structures in eutectic Sn-Pb and Bi-Pb alloys deformed to elongations of 2000% were presented in 1934 by Pearson Ref 5. This study was the first to identify an equiaxed grain morphology in the deformed regions and suggest that grain boundary migration may be involved in the deformation processes |
author2 |
McNelley, T.R. |
author_facet |
McNelley, T.R. McMahon, Michael Edward |
author |
McMahon, Michael Edward |
spellingShingle |
McMahon, Michael Edward Grain boundary development in superplastic aluminum alloys |
author_sort |
McMahon, Michael Edward |
title |
Grain boundary development in superplastic aluminum alloys |
title_short |
Grain boundary development in superplastic aluminum alloys |
title_full |
Grain boundary development in superplastic aluminum alloys |
title_fullStr |
Grain boundary development in superplastic aluminum alloys |
title_full_unstemmed |
Grain boundary development in superplastic aluminum alloys |
title_sort |
grain boundary development in superplastic aluminum alloys |
publisher |
Monterey, California. Naval Postgraduate School |
publishDate |
2012 |
url |
http://hdl.handle.net/10945/8452 |
work_keys_str_mv |
AT mcmahonmichaeledward grainboundarydevelopmentinsuperplasticaluminumalloys |
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1716806050796011520 |