Accession Number : ADA018128

Title :   Experimental Hysteretic Loss for a Series of Superconducting Filamentary NbTi Wires and a Field Dependent Critical State Model.

Descriptive Note : Final technical rept. 2 Oct 72-31 Dec 74,


Personal Author(s) : Ohmer,Melvin C. ; Wollan,John J. ; Lawson,Larry O.

Report Date : JUL 1975

Pagination or Media Count : 129

Abstract : This report summarizes the Air Force superconducting wire applications, the goals of future superconducting materials development, the state of the art theories of ac loss in superconductors, and the results of hysteretic loss measurements on a series of niobium titanium multifilamentary wires. Expressions were developed for magnetization and hysteretic loss for half cycle and full cycle for rod geometries for a critical state model with critical current inversely proportional to field. Bulk effects with surface like character are discussed along with surface shielding fields and the demagnetizing factor. The loss expressions of various models are compared to experimental loss. Universal loss curves constructed from experimental loss curves by appropriate normalization are obtained and used to predict loss accurately.

Descriptors :   *Superconductivity, *Superconductors, *Wire, Hysteresis, Losses, Magnet coils, Niobium alloys, Titanium alloys, Multiconductor cables, Magnetic fields, Rods, Magnetization

Subject Categories : Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE