Effect of lead loss and sheath structure on phase formation and alignment in (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10+{delta}}/Ag composite conductors
- Argonne National Lab., IL (United States)
The effects of metallic constituent evaporation and sheath structure on grain growth and alignment in silver-sheathed (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10+{delta}} (Bi-2223)/Ag composites have been investigated by inductively coupled plasma/atomic emission spectroscopy (ICP/AES), X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy. Specimens of Bi-2223/Ag composites fabricated by the oxide-powder-in-tube technique were peeled (opened) lengthwise to expose the ceramic powder core, and then heat-treated in 0.075 atm of oxygen for selected temperatures and times. The results were compared with those for as-processed samples with closed silver sheaths treated under identical conditions. ICP/AES analysis indicated that lead was the only metallic element to undergo substantial evaporation during annealing of opened samples. The lead-release process in parallel with the Bi-2223 formation reaction had an activation energy of {approximately}25 kJ/mol. Lead loss from the opened samples resulted in incomplete conversion to Bi-2223. The combined results show that the silver sheath effectively prevents evaporative lead loss, preserves and promotes densification, and induces texturing of the layered phases.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- DOE Contract Number:
- W-31109-ENG-38
- OSTI ID:
- 131545
- Journal Information:
- Journal of the American Ceramic Society, Vol. 78, Issue 10; Other Information: PBD: Oct 1995
- Country of Publication:
- United States
- Language:
- English
Similar Records
Search for a silver-sheathed 1212-type superconductor with a grain colony microstructure : M{sub 1}Sr{sub 2}Y{sub 1-x}Ca{sub x}Cu{sub 2}O{sub z} with M = (Bi,Pb), (Cd,Pb), and (Fe,Pb).
Reaction induced texture of (Bi,Pb)[sub 2]Sr[sub 2]Ca[sub 2]Cu[sub 3]O[sub 10+[delta]] /Ag composite conductors
Related Subjects
COMPOSITE MATERIALS
MICROSTRUCTURE
BISMUTH OXIDES
LEAD OXIDES
STRONTIUM OXIDES
CALCIUM OXIDES
COPPER OXIDES
SILVER
SUPERCONDUCTING WIRES
HIGH-TC SUPERCONDUCTORS
HEAT TREATMENTS
GRAIN GROWTH
EVAPORATION
LEAD
ICP MASS SPECTROSCOPY
X-RAY DIFFRACTION
SCANNING ELECTRON MICROSCOPY
X-RAY SPECTROSCOPY