PREPARATION OF HIGH-DENSITY AQUEOUS SUSPENSIONS
AND THE MOLDING OF PREFORMS FROM LITHIUM
E. I. Suzdal’tsev
Translated from Ogneupory i Tekhnicheskaya Keramika, No. 11, pp. 10 – 22, November, 2002.
Preparation of high-density, sedimentation-stable aqueous suspensions and preforms, based on lithium alumi
nosilicate glass, using a method of slip casting into porous molds is reported. Properties of slips under differ
ent conditions of grinding and stabilization are considered depending on the grinding-body-to-material weight
ratio, the amount of dispersion medium added, and the technology for processing lumpy raw material. The
wall thickness growth rate in preforms is measured in relation to slip parameters. Measures that would enable
control over slip properties with a view to optimizing the slip casting technology are proposed.
High-density water suspensions have been studied in a
number of works [1 – 8]. In those works, emphasis was
placed mainly on the rheological properties of suspensions
without considering their potential use for manufacturing
precursor materials. In our opinion, the preparation of aque-
ous slips from multicomponent glasses has not yet received
Little data (if any) have been reported in the literature on
the preparation of highly concentrated slips based on LAGs,
despite the ever-increasing interest in the technology for
preparation of glass-ceramic materials [9 – 17] possessing a
number of advantages over traditional glass-making tech
niques [18 – 24].
For this reason, studies of aqueous LAG-based slips have
significant practical implications in providing ways toward
manufacturing a wide range of commercial products.
The present work is concerned with the role and relation
ship of various technological factors in the production of
sedimentation-resistant highly concentrated LAG-based sus
pensions and their use for molding large-size components,
– identifying raw materials for preparation of slip and
glass ceramic (either amorphous precursor glass, or devi
– specifying, in qualitative and quantitative terms, the
suspension medium for grinding material;
– determining the grinding body-to-material ratio for
charging into the mill;
– determining the optimum fineness of grinding and the
sizing pf slip particles;
– monitoring the slip properties during stabilization;
– monitoring the wall thickness growth in preforms with
regard for slip properties;
– optimizing the casting parameters and properties of
– optimizing the technology for preparation of high-den-
sity, sedimentation-resistant slips from multicomponent
glasses and of high-quality preforms.
The precursor material was crushed on a jaw crusher into
lumps to a size not exceeding 15 ´ 15 ´ 5 mm and then
ground in a ball mill lined on the inside with corundum plate.
The grinding bodies were corundum balls 15 to 40 mm in di
ameter. The dispersion medium was distilled water (neat or
acidified to pH = 2.0) and ethanol.
The rheological properties of slips were determined us
ing a Volarovich rotary viscosimeter equipped with coaxial
cylinders and a Engler viscosimeter. The hydrogen ion con
centration and the electrokinetic potential of slips were mea
sured using an I-160 laboratory ionometer. The grain compo
sition of the slip’s solid phase was determined by a sedimen
tation method, and the density of molded preforms and the
wall thickness rate were determined using standard methods.
The grain composition of dry-ground materials was deter
mined by screening through a nest of sieves.
A specific feature of the wet-grinding technology is that
the crushing of lumpy material and its fine grinding are ef
fected using the same processing unit. It was established dur
ing the course of experiments that the optimum grinding-
Refractories and Industrial Ceramics Vol. 43, Nos. 11 – 12, 2002
1083-4877/02/1112-0332$27.00 © 2002 Plenum Publishing Corporation
Tekhnologiya Federal State Unitary Production and Research En
terprise, Obninsk, Kaluga Region, Russia.