STRUCTURAL CHANGES IN BINDER DURING OXIDATION
OF PERICLASE-CARBON REFRACTORIES
K. I. Ikonnikov,
A. A. Kondrukevich,
N. S. S’emshchikov,
A. V. Belyakov,
and M. L. Kostochka
Translated from Novye Ogneupory, No. 7, pp. 61 – 64, July, 2016.
Original article submitted May 26, 2016.
Results are given for the change in binder structure in periclase-carbon refractories during heat treatment in an
oxidizing atmosphere. After total burn-off at 1000°C carbon, securing periclase grains, the reduction in refrac
tory strength in compression measured at room temperature is 64% of the original, but an object does not dis
integrate. An inorganic chemical bond plays the role of a binder consisting of very fine calcium and iron sili
cates and fine fractions of magnesium, calcium, and iron oxide solid solutions. The results obtained make it
possible to predict more reliably the change in refractory properties in service proceeding from the raw mate
rial components used.
Keywords: periclase-carbon (PC) objects, carbon-containing components (CC), binder, flaky graphite, peri-
clase, steel-pouring ladle.
Recently there has been extensive study of reaction
mechanisms for carbon-containing components (CC) with
the main phase in periclase-carbon (PC) materials. Accord-
ing to numerous sources [1 – 4] their role includes prevent-
ing slag infiltration into refractory material since CC exhibit
low slag wettability. Gaseous oxidation products of carbon
fill pores and create counter pressure preventing slag pene
tration. Reduction of magnesium oxide to metal or volatile
suboxides additionally increase gas pressure in component
pores. In addition, at the boundary between a slag layer and
unchanged areas of PC-objects unchanged with respect to
composition formation is established of a dense layer of
secondary MgO [1, 2]. Due to gas transport reaction of
magnesium and its volatile suboxides they are trans
ferred into a colder layer of a PC object, oxidized to
MgO with air oxygen, penetrating from the outer side of
a refractory. Magnesium oxide separates in PC refractory
pores, forming a dense layer within them preventing pen
etration of air oxygen towards the boundary with molten
slag. It is also noted that introduction of graphite consider-
ably increases MgO–C object thermal shock resistance.
According to data in [3, 4] it has been established that
during heat treatment of PC materials there is partial coking
of carbon-containing component with formation of a carcase
bonding MgO grains. However, this does not reflect entirely
the mechanism of CC refractory structure formation. Re
cently in many metallurgical enterprises a trend has been
noted in transition from the lining of a working layer at the
bottom of a steel-pouring ladle made from refractory pieces
Refractories and Industrial Ceramics Vol. 57, No. 4, November, 2016
1083-4877/16/05704-0384 © 2016 Springer Science+Business Media New York
Proceedings of the International Conference of Refractory
Workers and Metallurgists (7 – 8 April 2016, Moscow).
OOO VPO Stal’, Odinstovo, Moscow Region, Russia.
FGBOU VO D. I. Mendeleev Russian Chemical-Technologi
cal University, Moscow, Russia.
ANO Chemical Expertise Center, Moscow, Russia.
Fig. 1. Appearance of PC objects after heat treatment in an oxidizing atmo