Ceramics

There are two recent rheological studies of dental ceramic materials which may be of interest.

2010

Rheological properties of concentrated aqueous fluorapatite suspensions. Albano MP, Garrido LB. 2010. Ceramics International 36 (2010) 1779-1786

Steady state flow was measured over shear range 0.5-542 reciprocal seconds using a concentric cylinder viscometer (Haake VT550,Germany). A yield stress was observed, followed by shear thinning behaviour. The effect of volume fraction on yield stress and limiting viscosity values was demonstrated and related to flocculation mechanism.


2009

Determination of the particle interactions, rheology and the surface roughness relationship for dental restorative ceramics.
Journal of the European Ceramic Society, Volume 29, Issue 14, November 2009, Pages 2959-2967 M. Kes, H. Polat, S. Kelesoglu, M. Polat, G. Aksoy

A commercial dental ceramic powder, IPS Empress 2 veneer powder, was tested as the raw material with slurries produced using different concentrations of electrolyte solutions of sodium chloride and calcium chloride. Apparatus was a Brookfield DV 111+ rheometer (with ULA adapter). Shear rate range was 0-140 reciprocal seconds. Temperature was not reported.
Dental ceramic slurries showed Newtonian behaviour when no electrolytes were present but non-Newtonian in the presence of electrolytes indicating respectively the absence or presence of flocculation. The effect on surface roughness and contact angle was also demonstrated.