Effects of isothermal annealing on the microstructure and on the superconductivity of two amorphous Be-Zr alloys

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1985

OSTI ID:5832625

Heh, J P

This thesis presents the measurement results of isothermal annealing experiments on the amorphous alloys Be-Zr (30 a/o and 40 a/o Be), in which the critical current density, J/sub C/, was correlated with changes in the microstructure. The superconducting transition temperature, T/sub C/, and upper critical magnetic field, H/sub C2/, are less structure-sensitive parameters. However, they were also monitored in the course of this study. In addition, the superconducting parameters such as the zero-temperature coherence length (Xi(0), and the Ginzburg-Landau (GL) parameter, kappa, etc., were calculated on the basis of the measured quantities, T/sub C/, the electrical resistivity, rho, and the temperature gradient of the upper critical magnetic field at temperatures near T/sub C/, i.e., (dH/sub C2//dT)/sub T = T/sub C//. The microstructure of the studied samples was determined by x-ray, transmission electron microscopy (TEM), and scanning electron microscopy (SEM) observations. The former two techniques were utilized to search for evidence of crystallization, whereas the later provides information of the surface condition for samples used in this investigation.

• Research Organization: Pennsylvania State Univ., University Park (USA)
• OSTI ID: 5832625
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
360104 -- Metals & Alloys-- Physical Properties
ALLOYS
ANNEALING
BERYLLIUM ALLOYS
COHERENCE LENGTH
CRITICAL FIELD
CRYSTAL STRUCTURE
DIMENSIONS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
GINZBURG-LANDAU THEORY
HEAT TREATMENTS
LENGTH
MAGNETIC FIELDS
MICROSTRUCTURE
PHYSICAL PROPERTIES
SUPERCONDUCTIVITY
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE
ZIRCONIUM ALLOYS