Grain boundary development in superplastic aluminum alloys
By: Michael E. McMahon
Publisher: Naval Postgraduate School; Available from National Technical Information Service
Published: 1996
Place of publication: Monterey, Calif; Springfield, Va
Language: eng
Number of pages: 206
Description: 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.
Notes: Dissertation supervisor(s): T.R. McNelley.

"December 1996."

Dissertation (Ph.D. in Mechanical Engineering) Naval Postgraduate School, December 1996.

Includes bibliographical references (p. 195-203).

Also available online.

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US Navy (USN) author.

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