No abstract

No abstract

No abstract

No abstract

We show, for the first time, that a dc electric field of 20 V/cm shifts the densification curve to a lower temperature in constant heating rate experiments with yttria‐stabilized tetragonal zirconia powder (3Y‐TZP). The enhanced sintering rate is ascribed, at least in part, to the reduced rate of grain growth under the applied field, consistent with earlier experiments on the influence of such fields on grain size in superplastic deformation and isothermal grain growth in zirconia polycrystals.

No abstract

No abstract

A model for the particle-particle interaction in a chain of spherical particles in an electrorheological (ER) fluid is developed based on an expansion of the potential which satisfies the Laplace equation. The electric-field distribution and force-distance relationship between particles are calculated as a function of Kp/Kf (the dielectric constant of the sphere relative to that of the medium) and particle-particle spacing using this model. The calculations predict electric-field concentrations of about an order of magnitude near particle contacts. This gives a force between particles that is approximately an order of magnitude higher than predicted by the classical point-dipole approximation, and is in reasonable agreement with that measured experimentally. Subtle effects of the carrier fluid on the interaction force and an explanation for the non-Ohmic behavior of ER fluids are deduced in terms of its dielectric constant and dielectric strength.