The compatibility of glass and refractory depends on the
chemical composition of the glass and of the refractory.
Some oxides are considered basic and some are considered
acidic, and there is a formula which you can use to find
where any particular refractory composition falls on the
acid-base axis. You do the same for the particular type of
glass you have, and choose a refractory that is compatible
with that glass. (E.g., an acid glass or slag will quickly corrode
a basic refractory.)
Sorry, but I cannot find a good on-line source for this.
You might consider buying a refractory handbook.
You should definitely get in contact with a refractory
manufacturer. They can advise you on this.
(Harbison-Walker, A. P. Green, North American
Refractories Company, etc.)
You might want to attend the Glass Problems Conference
at Ohio State in October. There are usually a lot of
glass industry vendors there and they have hospitality
suites. (Although the industry is in financial trouble, and
the hospitality may not be as lavish as it once was.)
Olin Perry Norton
I know that glass/refractory compatibility is the point but I am
starting for the scratch so I have to investigate first the refractory
market in that field of temperature. Products which could work in that
temperature zone are not a lot. and further researches will be necessary
to perform tests with samples of available candidates.
I spoke with people from Saint-Gobain SEFPRO and it seems that THTZ
materials could be also on the line.
Anyway, I will contact kiln manufacturers and Engineering firms which
specialize on that field.
Sorry for the conference in Ohio, I am living in Europe and I am afraid
I'll be a little busy in October.
Sorry, I didn't notice you were from Europe. The Glassman Europe meeting
would be good, but it is held every other year, so you would have to wait
until 2011 for the next meeting. On the other hand, you might enjoy
Sao Paulo if you went to the Glassman South America meeting in March
I repeat my suggestion that you contact refractory suppliers. The ones
supply the glass industry know which types of refractory are best for
Also, a good refractory handbook will have useful information about
What type of glass are you dealing with? Regular soda-lime glass?
Olin Perry Norton
It is about Investigation on glass-ceramics (LAS + nanocrystallization)
I am afraid that a Handbook wouldn't address properly refractory
materials to that zone of working temperatures in glass manufacture. In
addition, specific elements of the glass composition (alone or combined)
introduce specific refractory behaviouring concerning
reaction/corrosion. Moreover, glass surface quality must be insured with
processing elements in contact.
Actually, according with refr. manufacturers that I already contacted
(RHI, Saint-Gobain SEFPRO R&D...) we are on the borderline of
capability for existing materials. Thus, some lab experiments must be
done to select the more suitable ones to a potential use on a production
line by starting probably with very High Zicronia Content kinds (HZ)
like RHI Monofrax® Zs Brands if I can't find better.
In the past the usual way to work at such temperatures was to use a
metal like molybdenum and a reducing atmosphere. It's a bit OTT for
the precious metals, like Pt60/Rh40. The fused silica people have some
relevant experience. Iso-statically pressed Chromic Oxide and related
refractories are the only ones that might work at the limit in air or
However there can be complications if you have Arsenic or Lead in the
glass. Both cause trouble with corrosion of the Molybdenum.
According with the information collected form manufacturers, high
Zirconia content electro-fused ref are suitable to such temperature.
Further tests are needed but RHI Monofrax® Zs Brands and Saint-Gobain
SCIMOS Z are privilegied candidates for the melting zones.
Now, I am investigating to find materials suitable for the forming zone
with a pasty glass at 1450ºC. The aim is to produce 1 m x 1 m plates.
Max thickness 20 mm with tolerance of 0.1 mm
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