Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

On the microstructural aspects of the nonhomogeneity of superplastic deformation at the level of grain groups

Journal Article · · Acta Metallurgica et Materialia
;  [1];  [2];  [3]; ;  [4]
  1. Ufa Aviation Inst., Ufa (Russian Federation). Dept. of Materials Science
  2. Inst. of Metals Superplasticity Problems, Ufa (Russian Federation)
  3. Warsaw Univ. of Technology (Poland). Inst. of Materials Science and Engineering
  4. Univ. of California, Davis, CA (United States). Dept. of Mechanical, Aeronautical and Materials Engineering
The surface relief of a superplastically deformed magnesium alloy (Mg-1.5%Mn-0.3%Ce) was studied. Zones/bands of localized deformation were detected by means of vacuum etching. Between the localized deformation bands were less-deformed regions. After 20% elongation in vacuum (1.33 {times} 10{sup {minus}3}Pa), zones of intensive vacuum etching were observed as two intersecting bands of localized deformation oriented at 35--60{degree} to the tensile axis. Spacing between the localized deformation bands is 6--8 grain diameters after a tensile elongation of 20% and 3--4 grain diameters after an elongation of 160%. The observed bands of strain localization are explained from the viewpoint of cooperative grain boundary sliding, i.e., shifting of grain groups as a whole unit along grain boundary surfaces oriented close to the maximum shear stress direction. It is suggested that the cooperative nature of GBS be taken into account when evaluating the real local strain rate and the real strain-rate sensitivity of grain boundary sliding process.
OSTI ID:
143897
Journal Information:
Acta Metallurgica et Materialia, Journal Name: Acta Metallurgica et Materialia Journal Issue: 1 Vol. 42; ISSN 0956-7151; ISSN AMATEB
Country of Publication:
United States
Language:
English

Similar Records

The role of deformation localization in superplastic flow
Journal Article · Mon Aug 01 00:00:00 EDT 1994 · Acta Metallurgica et Materialia; (United States) · OSTI ID:7019504

Observations of grain-boundary sliding and surface topography in an 8090 Al alloy after uniaxial and biaxial superplastic deformation
Journal Article · Thu Dec 31 23:00:00 EST 1998 · Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science · OSTI ID:316069

The role of partial melting on superplasticity of Si{sub 3}N{sub 4}p/Al-Cu-Mg composite
Journal Article · Sun Feb 13 23:00:00 EST 2000 · Scripta Materialia · OSTI ID:20023087