Sciencemadness Discussion Board

High emissivity furnace coating

Twospoons - 1-6-2005 at 20:55

Finally stumbled onto a formula for a high emissivity furnace coating.
Quote:

United States Patent 4,469,721ShioyaSept. 4, 1984
------------------------------------------------------------------------
High emissivity refractory coating, process for manufacturing the same, and
coating composition therefor
Inventors: Shioya; Kiyohiko (No. 19-7, Azabujuban 2-chome, Minato-ku, Tokyo,
JP). Appl. No.: 501,360Filed: Jun. 6, 1983Intl. Cl. : C09D 1/02Current U.S.
Cl.: 427/397.8; 501/89; 501/97Field of Search: 106/84; 501/89, 97; 427/397.8,
397.7
------------------------------------------------------------------------
References Cited | [Referenced By]

------------------------------------------------------------------------
U.S. Patent Documents
2,806,005Sept., 1957White501/89 X3,615,782Oct., 1971Bawa et
al.106/843,892,584Jul., 1975Takeda et al.501/89

Foreign Patent Documents
15927Feb., 1980JP501/8923024Feb., 1980JP501/89Primary Examiner: Kaplan; G. L.
Attorney, Agent or Firm: Sughrue, Mion, Zinn, Macpeak, and Seas

------------------------------------------------------------------------
Abstract

------------------------------------------------------------------------


A high emissivity refractory coating comprising a cured coating composition
comprised of a powder mixture containing 17 to 22% by weight of silicon
carbide, 6 to 11% by weight of graphite, 17 to 22% by weight of aluminum
oxide, 2 to 5% by weight of silicon nitride, 8 to 12% by weight of tricobalt
tetroxide, 18 to 22% by weight of cobalt aluminum oxide and 18 to 23% by
weight of ferrosilicon, and an aqueous solution of potassium silicate. The
high emissivity refractory coating is applied onto the surface of furnace
refractories or ceramic fibers. The coating does not peel from the surface of
the furnace wall and increases the energy efficiency of the furnace.



In general, all the refs I've seen for high E refractories seem to indicate SiC, carbon, or various nitrides as components, SiC being most common.

Pyridinium - 2-6-2005 at 19:35

I would love to see such a coating tested on a homebuilt firebrick kiln.

Silicon carbide- you can get 1000 grit (I think, maybe even 1200) for rock polishing and grind it even finer. Even materials that are too hard for a mortar and pestle can be pulverized to dust with practice. I've done it with sand in a porcelain mortar and pestle.