Accession Number : AD0625023

Title :   SOME ASPECTS OF DISLOCATION DYNAMICS IN METALS AND THE INFLUENCE OF DISLOCATION DISTRIBUTION ON LOW TEMPERATURE ELECTRICAL TRANSPORT PROPERTIES,

Corporate Author : STANFORD UNIV CALIF DEPT OF MATERIALS SCIENCE

Personal Author(s) : Barbee,Troy W. ,Jr.

Report Date : NOV 1965

Pagination or Media Count : 230

Abstract : The relationship between dislocation dynamics and strain hardening was investigated in polycrystalline Ta, Mo, Fe-Si, Cu, Al and single crystal LiF by determining the strain dependence of the dislocation velocity exponent m, using the macroscopic stress-relaxation technique. Dislocation structures in tantalum resulting from deformation to various values of strain at room temperature, deformed at temperatures between 400 and 1000 C, and deformed at room temperature and annealled at temperatures between 400 and 1200 C were examined by transmission electron microscopy techniques. The relationship between dislocation distribution and the low temperature electrical transport properties of metals was also investigated. The effect of dislocation distribution on the properties of high field superconductors was also considered. Calculations were made in which the effects of the strain fields of individual dislocations and the effects of dislocation distribution on the spatial variation of the conduction electron mean free path on the properties of Type I and Type II superconductors were considered.

Descriptors :   (*CRYSTAL DEFECTS, METALS), (*TANTALUM, CRYSTAL DEFECTS), ELECTRICAL RESISTANCE, MOLYBDENUM, IRON ALLOYS, SILICON, COPPER, ALUMINUM, ELECTRON MICROSCOPY, SINGLE CRYSTALS, LITHIUM COMPOUNDS, FLUORIDES, CRYOGENICS, STRAIN HARDENING, DEFORMATION, DYNAMICS, RELAXATION, STRESSES, STRAIN(MECHANICS)

Subject Categories : Metallurgy and Metallography
      Crystallography
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE