Microstructure development in bronze route Nb/sub 3/Sn and (Nb,Ta)/sub 3/Sn multifilamentary composites
Electron microscopy has been used to characterize the microstructure of commercial binary and ternary A15 multifilamentary composites. TEM sections have been prepared using ion beam milling from samples reacted for various times at temperatures in the range 650800/sup 0/C. Layer growth kinetics have also been investigated using a combination of SEM and low temperature inductive measurements. The presence of a band of columnar grains adjacent to the refractory core is confirmed in all cases and is particularly marked at the lower temperatures. As layer growth proceeds, the columnar structure develops into an equiaxed grain structure; the mean grain size depends on the core composition. On the basis of this microstructural investigation and precise measurements of filament volume and length changes during reaction, it is proposed that the mechanism for microstructure modification is stress driven grain boundary sliding. A model describing this process is summarised.
- Research Organization:
- Department of Metallurgy and Materials Science, University of Cambridge, Pembroke Street, Cambridge
- OSTI ID:
- 6484794
- Report Number(s):
- CONF-840937-
- Journal Information:
- IEEE Trans. Magn.; (United States), Vol. MAG 21:2; Conference: Applied superconductivity conference, San Diego, CA, USA, 9 Sep 1984
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
GENERAL PHYSICS
36 MATERIALS SCIENCE
SUPERCONDUCTING COMPOSITES
CHEMICAL REACTION KINETICS
CRYSTAL GROWTH
CRYSTALLOGRAPHY
MICROSTRUCTURE
BRONZE
CRYSTAL MODELS
FILAMENTS
GRAIN BOUNDARIES
NIOBIUM ALLOYS
SCANNING ELECTRON MICROSCOPY
SLIP
SUPERCONDUCTING WIRES
TANTALUM ALLOYS
TIN ALLOYS
TRANSMISSION ELECTRON MICROSCOPY
ALLOYS
COMPOSITE MATERIALS
COPPER ALLOYS
COPPER BASE ALLOYS
CRYSTAL STRUCTURE
ELECTRON MICROSCOPY
KINETICS
MATERIALS
MATHEMATICAL MODELS
MICROSCOPY
REACTION KINETICS
WIRES
420201* - Engineering- Cryogenic Equipment & Devices
360102 - Metals & Alloys- Structure & Phase Studies