Accession Number : AD0756416

Title :   Measurement and Analysis of Thermal Inhomogeneities Developed During the Plastic Deformation of Copper,

Corporate Author : BALLISTIC RESEARCH LABS ABERDEEN PROVING GROUND MD

Personal Author(s) : Moss,Gerald L.

Report Date : SEP 1972

Pagination or Media Count : 210

Abstract : A photon detection system was designed and calibrated for the measurement of thermal changes encountered during the plasticity of metals. Calibrations were made of the thermal response of the detection system, the optical effects of changes in surface topography and changes in the thermal radiating characteristics of a metal that arise during plasticity. Then the radiant energy emitted from electrolytic tough pitch copper during plastic extension was recorded with the photon detection system. Abrupt changes in emission were correlated with the intermittent plastic action of Luders bands. The tendency for plasticity to continue to develop by the functioning of individual Luders bands throughout deformation to fracture was established with radiation measurements. The conversion of mechanical work into heat was considered in terms of dislocation motion and annihilation. Two new models of energy conversion through dislocation annihilation were developed to account for heating. The localized temperature changes developed within Luders bands during plasticity were estimated from the radiation data. (Author)

Descriptors :   (*METALS, PLASTIC PROPERTIES), (*COPPER, DEFORMATION), THERMAL ANALYSIS, INFRARED DETECTORS, SPECTRUM SIGNATURES, DISLOCATIONS, THESES

Subject Categories : Metallurgy and Metallography
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE