HIGH-ALUMINA COMPOSITE CONCRETES AND COATINGS
BASED ON MODIFIED PHOSPHATE BINDER SUSPENSIONS
Yu. N. Trepalina,
V. A. Doroganov,
and E. I. Evtushenko
Translated from Novye Ogneupory, No. 8, pp. 36 – 39, August 2011.
Original article submitted July 1, 2011.
Coatings and materials based on aluminum phosphate suspensions are studied that have high strength in a raw
state and are suitable for carrying out combined firing of a refractory and coating. An aluminum phosphate
binder provides preparation of high physicomechanical properties in the firing temperature range. Use of tra
ditional mixes with a protective aluminum phosphate coatings, and also ceramic concrete based on this binder
provide increased material corrosion resistance, and consequently an increase in object operating life and pe
riod between repairs for metallurgical and glass melting units.
Keywords: aluminum phosphate binder, corrosion resistance, protective coatings, mechanical activation,
composite materials, slag, slag resistance, working surface wetting capacity, glass melting.
Phosphate binders are used traditionally both as a binder
in preparing refractory ceramic concretes and in the form of
protective coatings [1 – 5]. Their use makes it possible to re-
duce the firing temperature during preparation of refractory
concrete materials, and to increase refractory concrete life in
service. The purpose of protective coatings on refractories is
very varied. There are coatings that are chemically resistant,
antiburning, gas protective, etc. The service life of a coating
depends on operating conditions and is from several seconds
to many days. The choice of a protective coating in each spe-
cific case should be made in relation to the nature of the cor
rosive medium and the nature of the material being coated,
Coatings should be refractory and resistant sharp tempera
ture variations and mechanical action .
Phosphate binders are highly refractory substances, pre
pared as a result of chemical reaction that occurs between
orthophosphoric acid and finely ground aluminum-, chro
mium-, aluminum-chromium-containing or aluminum sili
cate materials . In this work in order to prepare modifying
coatings a suspension of aluminum phosphate composition
was used, which has increased strength in a raw condition,
and therefore it becomes possible to heat treat an object and
In developing protective coatings three types of materials
and binders were studied:
– aluminum phosphate binders, which are used as a pro
tective coating, and also a ceramic concrete matrix;
– ceramic concretes based on an aluminum phosphate
binder developed using high alumina chamotte as a filler;
– composite materials prepared on the basis of a ram-
ming grade MMK-80 (plant control composition) produced
in OAO Semiluk Refractory Plant.
Aluminum phosphate binders were prepared by com-
bined grinding of components in a ball mill of periodic oper-
ation with a volume of 8 liters with orthophosphoric acid
with an apparent density of 1140 kg/m
in a ratio of 75%
solid and 25% liquid phase. The solid phase used was
electromelted corundum with an Al
content not less than
97%. Binder dispersion was specified by a content of parti-
cles on a 0063 screen (less than 63 mm) not more than 2%.
Combined milling of binder components provided with me
chanical activation improvement of the suspension quality
Ceramic concretes based on aluminum phosphate binder
were prepared on the basis of an experimental composition,
containing 65% high alumina chamotte (filler) and 35% alu
minum phosphate binder. Specimens were molded by vibra
tion casting and then dried at 100°C.
Composite materials prepared on the basis of ramming
mix grade MMK-80. Specimens of this material are refrac
tory substrates and cubes with an edge size of 30 mm molded
by a static method under a pressure of 40 MPa. The ramming
mix grade MMK-80 consists of 75% high-alumina chamotte
and 35% binder. The binder used in preparing substrates and
cubes was a combined milling mixture (CMM), conditioned
with addition of orthophosphoric acid with a density of
; CMM consisting of 30% clay grade LT-0 from
the Latnenski deposit, and 70% electromelted corundum,
was prepared by dry combined milling in a tube mill.
In order to carry out testing of the materials cubic speci
mens were formed with an edge size of 50 mm and a depres
Refractories and Industrial Ceramics Vol. 52, No. 4, November, 2011
1083-4877/11/05204-0291 © 2011 Springer Science+Business Media, Inc.
V. G. Shukhov Belgorod State Technological University, Belgo