Accession Number : ADA616535


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


Descriptive Note : Journal article


Corporate Author : AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE


Personal Author(s) : Konkova, Tatyana ; Valeev, Irshat ; Mironov, Sergey ; Korznikov, Alexander ; Myshlyaev, Michail ; Semiatin, S L


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a616535.pdf


Report Date : Nov 2014


Pagination or Media Count : 15


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.


Descriptors :   *COPPER , *ELECTRIC CURRENT , *GRAIN STRUCTURES(METALLURGY) , *MICROSTRUCTURE , BACKSCATTERING , COOLING , CURRENT DENSITY , DIFFRACTION , GRAIN SIZE , HEATING , MICROHARDNESS , PULSES , RECRYSTALLIZATION , TEMPERATURE , TEXTURE


Subject Categories : Properties of Metals and Alloys
      Crystallography
      Electricity and Magnetism


Distribution Statement : APPROVED FOR PUBLIC RELEASE