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Metallurgical Transactions A

, Volume 23, Issue 11, pp 3135–3140 | Cite as

Interaction of high-temperature deformation mechanisms

  • M. G. Zelin
  • H. S. Yang
  • R. Z. Valiev
  • A. K. Mukherjee
Mechanical Behavior

Abstract

High-temperature tensile tests have been conducted on a magnesium alloy (Mg-1.5 pct Mn-0.3 pct Ce) with randomly mixed fine and coarse grains. The microstructural examinations clearly show that different mechanisms operate in the regions of coarse and fine grains. The coarse grains deform by dislocation slip, while grain boundary sliding occurs in the fine grains. The influence of these mechanisms on each other has also been observed in terms of dislocation density, intragranular slip lines, and grain boundary sliding. The analytical equations describing the interaction of two deformation mechanisms operative in materials with regions of fine and coarse grains were derived. The analysis is applicable for determining the controlling mechanism of two interacting mechanisms. It is predicted that at a critical volume fraction of fine grains of approximately 40 pct, a transition from superplastic to nonsuperplastic behavior occurs.

Keywords

Metallurgical Transaction Magnesium Alloy Deformation Mechanism Dislocation Slip Transmission Electron Microscope Photograph 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© The Minerals, Metals and Materials Society, and ASM International 1992

Authors and Affiliations

  • M. G. Zelin
    • 1
  • H. S. Yang
    • 1
  • R. Z. Valiev
    • 1
  • A. K. Mukherjee
    • 2
  1. 1.Department of Mechanical, Aeronautical and Materials EngineeringUniversity of California-DavisDavis
  2. 2.Ufa Aviation InstituteUfaRussia

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