Jeff Lawrence on thu 19 apr 01
Hi,
My boy's soccer coach's day job is a scientist and he posed me a ceramic
question that stumped me.
He has tubes of "superalloy" (mostly nickel with the rest made up of cobalt
and chromium) which fit closely into cylindrical holes with tolerances a few
thousandths of an inch. The tubes will be heated to about 1000C during some
subsequent process. He would like a ceramic liquid that is insinuating
enough to wick down the gap between tube and wall so that it would melt
between the tube and cylinder when heated and fuse the two together when
cooled.
Can a glaze be ground that fine?
Would sodium silicate work?
Has anyone dissolved silicates in oil?
Thanks in advance for any help!
Jeff Lawrence ph. 505-753-5913
18496 US HWY 84/285 fx. 505-753-8074
Espanola, NM 87532 jml@cybermesa.com
iandol on sat 21 apr 01
Dear Jeff,
Is it necessary to use an insulating material for this application? If =
not, then either Stoody or Wall Colmonoy would be able to provide a =
compatible brazing alloy for the purpose of fixing one into the other. =
Both companies manufacture the alloys you are talking about. They will =
need to know the future service temperature, potential stress levels and =
environment.
Otherwise, someone will need to design a ceramic sealing material which =
has compatible Coef of Linear Expansion.
All the best,
Ivor=20
Logan Oplinger on sat 21 apr 01
Jeff,
Hmmm, 1000C x 1.8F/C + 32F = 1832 F.
Not sure what the maximum particle size of prepared commercial glazes are, but I would assume these would be preferable. Would glaze have adequate wetting property when melted to be used on metal? Also need to consider coeffficient of expansion differences between metal and glaze (glass).
Also, what is end use of assembled product? Will join be exposed to corrosive environment, aqueous solutions?
Sodium silicate would eventually be re-disolved in water solutions.
What is the material into which the tubes are inserted?
If it is metal, a high temperature brazing metal may work (silver solder has different flowing temps and may work).
A web search may prove useful, looking for ceramic cements. Try Omega Engineering:
www.omega.com
Also look in the Thomas Register of American Manufacturers:
www.thomasregister.com
(My favorite!)
I don't have much time today to do a preliminary search, but will try later.
Good luck.
Logan Oplinger
------------------------------------------------------
Get the Latest News at CNN Interactive: http://CNN.com
ferenc jakab on sat 21 apr 01
>
> He has tubes of "superalloy" (mostly nickel with the rest made up of
cobalt
> and chromium) which fit closely into cylindrical holes with tolerances a
few
> thousandths of an inch. The tubes will be heated to about 1000C during
some
> subsequent process. He would like a ceramic liquid that is insinuating
> enough to wick down the gap between tube and wall so that it would melt
> between the tube and cylinder when heated and fuse the two together when
> cooled.
>
> Can a glaze be ground that fine?
> Would sodium silicate work?
> Has anyone dissolved silicates in oil?
Jeff,
I believe a majolica style glaze might do the job, but I worry about
expansion and contraction. I.e. the expansion and contraction of metal might
exceed that of ordinary glazes. I once created an emulsion of thick glaze
and vegetable oil to wet a stamp pad because the water based pad was drying
out too quickly while I was stamping the pots the stamped glaze worked well
on the raw terracotta.
Hope this helps,
Feri
Marshall on sat 21 apr 01
Hi,
Any light oil should be OK as a medium I'd say. This idea is based on the
fact that dentists make porcelain dentures using oil as a suspending agent
and fire them to about 1350 C in 15 mins.
Yours Will.
http://www.willlevimarshall.com/
Joseph Herbert on sun 22 apr 01
It is possible that the fluxing activity of the oxides in the glaze may not
be limited to the other ceramic constituents. At elevated temperatures some
of the glaze components may prefer to interact with the metals.
Joseph Herbert
Logan Oplinger on mon 23 apr 01
Jeff,
Hello again. More web sites to look at:
http://www.flexbar.com/productmenu_adhesives.htm
http://www.aremco.com
http://www.hottec.com/Bondceram/ceramicindex.html
And the following address:
Technical Products, Inc.
P.O. Drawer 189
Hubertus, WI 53033 USA
Tel: 800-869-2008
Carborundum Co., The, Monofax Refractories Div.
501-T New York Ave.
Falconer, NY 14733 1797 USA
Tel: 716-483-7200
Dylon Industries, Inc.
7700-T Clinton Road
Cleveland, OH 44144 1045 USA
Tel: 216-651-1300
Good hunting,
Logan Oplinger
...Previously, I provided the following addresses:
> A web search may prove useful, looking for ceramic cements. Try Omega Engineering:
> www.omega.com
>
> Also look in the Thomas Register of American Manufacturers:
> www.thomasregister.com
> (My favorite!)
------------------------------------------------------
Get the Latest News at CNN Interactive: http://CNN.com
| |
|
