Skip to main content Accessibility help
×
Home

Rheology of YBa2Cu3O7−x Precursors

  • Timothy M. Green (a1) and Mufit Akinc (a1)

Abstract

Nitrate and acetate precursors to Ba2Cu3O7−x (123) are prepared using a molten salt technique. The viscosity and shear stress of the paste are controlled by evaporation of water from the paste. The pastes contain ˜20 - 80 volume percent solids. Rheometry over strain rates of 0 - 200 sec−1 shows both systems are shear-thinning. Both systems are thixotropic. The nitrate system may be described by a two-stage Bingham Plastic model, the acetate by a Hershel-Bulkley model. The existence of more than one region of flow behavior suggests that there are at least two mechanisms which contribute to flow. In the low strain rate region, flow resistance is due to the existence of flocs in the colloidal assembly. At higher strain rates, flow is probably controlled by interlaminar drag interactions. Precursors produced by both methods have been used to form fibers of YBa2Cu3O7−x, by ram extrusion.

Copyright

References

Hide All
1. Maple, M. Brian, Mat. Res. Soc. Bull. 15, 20 (1989).
2. Clarke, D. R., Adv. Cer. Mat. 2, 273 (1987).
3. Vance, E. R., Ceramics International 16, 361 (1990).
4. Jin, S. and Graebner, J. E., Mat. Sci. and Eng. B 7, 243 (1991).
5. Millis, R., Cellikaya, A., Akinc, M., and McCallum, R., IEEE Trans. on Magnetics 25, 2550 (1987).
6. Green, T. M., Millis, R., and Akinc, M., 1990 Talk Summaries. Electronics Division, (American Ceramic Society, Westerville, OH, 1990), p. 155–SII.
7. Holcombe, C.E., Edwards, C.C. and Carpenter, D. A., New Yttria Plasters (Union Carbide Corp.- Nuclear Div., Oak Ridge Y-12 Plant, Oak Ridge, TN, 1978).
8. Millis, R. P., M.S. Thesis, Iowa State University, 1990.
9. Olphen, H. van, An Introduction to Clay Colloid Chemistry, 2nd ed. (John Wiley and Sons, New York, 1977), p. 137138.
10. Barnes, H. A., Hutton, J. F., and Walters, K., An Introduction tO Rheology, Vol.3 (Elsevier, Amsterdam, 1989), pp. 121126.

Rheology of YBa2Cu3O7−x Precursors

  • Timothy M. Green (a1) and Mufit Akinc (a1)

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed