INADEQUACIES OF VISCOSITY THEORIES FOR VITREOUS KNO3 - Ca(NO3)2.
CATHOLIC UNIV OF AMERICA WASHINGTON D C VITREOUS STATE LAB
Pagination or Media Count:
The viscosity of 60 NKO3 - 40 CaNO32 mole was measured by the beam-bending method and found to be Arrhenius with an activation energy of 138 Kcalmole. These new data were combined with previously reported capillary and rotation data and gave a smooth plot. The complete viscosity data were used to test the best-known viscosity theories but no reasonable fit was found. As a result of this study it was found that the temperature dependence of the viscosity is not controlled by structural effects such as free volume, configuration entropy, etc., but by activation energy effects in the viscous flow process. Finally, all theories are in error in predicting that the viscosity goes to infinity in the annealing region much faster than the measured values indicate. Author
- Physical Chemistry
- Ceramics, Refractories and Glass