RogueRose - 29-11-2016 at 00:44
I've found this product that is supposed to help reflect heat off the surface of refractory like brick or ceramics.
Here is a link to the product page:
https://secure.anvilfire.com/itc-100ht.html
Here is a PDF for the MSDS
https://secure.anvilfire.com/anvilfire-custom/DOCs/ITC/ITC-1...
Here are some other similar refractory "liners" / reflectors. They seem to be based on Al2O3 and SiO2. The % of alumina ranges from 43% to 93% and
the SiO2 is 6% to 50%.
http://plibrico.com/uploads/MSDS/sds%20Plistix%20900F.pdf
http://plibrico.com/uploads/MSDS/sds%20Plistix%20SR%2090.pdf
Some of these products seem to be a liquid and are "injectable" and they use sodium silicate which seems to be an ideal substance to make a "flowable"
liquid.
If anyone has any experience with this stuff I'd be interested in any input.
I'm looking to make something that I can line some cast refractory made of clay, sand, cement and perlite. The goal is to help reflect some of the
heat from the walls onto the material in the forge/kiln.
I'm thinking that a alumina/quartz/sodium silicate mixture possibly with a binding agent may be a workable solution.
DrP - 29-11-2016 at 02:45
Alumina silicate (Al2O3.Si2O4) or Mullite is very refractory as you seem to already know. It probably contains powdered mullite or even fibres to give
structure. There are tables you can look up which give you the thermal conduction or insulation values of materials - I believe that zirconium mullite
(Zirconia Silicate) is even more refractory than the aluminium one.
As for lining the walls of a furnace, I would use Alumina silicate ceramic fibre boards. The trouble with a coating is that it will still degrade with
the fire eventually. Sodium silicate and mullite mixtures need curing I think or they melt like glass as you approach 1000C. Like geopolymer cements.