Spheroidization Effects on the Electrical and Magnetic Properties of Cu-Nb Composites

Author

Sandim, Maria J R ; Sandim, Hugo R Z ; Stamopoulos, Dimosthenis ; Renzetti, Reny A. ; Das Virgens, Maurício G. ; Ghivelder, Luis

Author_Institution

Dept. de Engenharia de Materiais, FAENQUIL, Lorena

Volume

16

Issue

2

fYear

2006

fDate

6/1/2006 12:00:00 AM

Firstpage

1692

Lastpage

1695

Abstract

We report on the microstructure evolution in Cu-15% Nb multifilamentary wires upon annealing and the corresponding effects on their electrical and magnetic properties. During annealing at temperatures higher than 800degC thermal instability mechanisms take place in the microstructure of the Cu-15%Nb composite, leading to spheroidization, followed by coarsening of niobium filaments. Such microstructural changes exert considerable influence on the magnitude of the normal electrical resistivity for the Cu-Nb composite. In addition, the annealing process leads to a double-peak structure in the isothermal DC magnetization curves of the composite, which is strongly dependent on the annealing time. This behavior suggests that the spheroidization kinetics can be obtained from M(H) curves

Keywords

annealing; copper alloys; electrical resistivity; magnetisation; multifilamentary superconductors; niobium alloys; spheroidizing; thermal stability; Cu-Nb; annealing; electrical resistivity; isothermal DC magnetization curves; magnetic properties; microstructure evolution; multifilamentary wires; niobium filaments; spheroidization effects; thermal instability; Annealing; Electric resistance; Isothermal processes; Kinetic theory; Magnetic properties; Magnetization; Microstructure; Niobium; Temperature; Wires; Cu-Nb composites; electrical resistivity; magnetization; spheroidization;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/TASC.2005.864287

Filename

1643186