Effect of Electric-current Pulses on Grain-structure Evolution in Cryogenically Rolled Copper

Abstract

The effect of electric-current pulses on the evolution of microstructure and texture in cryogenically rolled copper was determined. The pulsed material was found to be completely recrystallized, and the recrystallization mechanism was deduced to be similar to that operating during conventional static annealing. The microstructural changes were explained simply in terms of Joule heating. A significant portion of the crystallization process was concluded to have occurred after pulsing; i.e., during cooling to ambient temperature. The grain structure and microhardness were shown to vary noticeably in the heat-affected zone (HAZ); these observations mirrored variations of temper colors. Accordingly, the revealed microstructure heterogeneity was attributed to the inhomogeneous temperature distribution developed during pulsing. In the central part of the HAZ, the mean grain size increased with current density and this effect was associated with the temperature rise per se. This grain size was slightly smaller than that in statically recrystallized specimens.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 2014
Accession Number
ADA616535

Entities

People

  • Alexander Korznikov
  • Irshat Valeev
  • Michail Myshlyaev
  • Sergey Mironov
  • Sheldon Lee Semiatin
  • Tatyana Konkova

Organizations

  • Air Force Research Laboratory

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Annealing
  • Boundaries
  • Crystallography
  • Current Density
  • Electric Current
  • Grain Size
  • Hardness
  • Heat Energy
  • Materials
  • Materials Processing
  • Mechanical Properties
  • Microhardness
  • Microstructure
  • Phase Transformations
  • Recrystallization

Fields of Study

  • Materials science

Readers

  • Metallurgy
  • Plasma Physics.