I was looking through the McMaster Carr catalog and came
across this material called  Toughened Zirconia Ceramic.
Five times the fracture toughness of alumina.
254,000 psi compressive strength.
90,000 psi flexural strength.
932 degrees F.

$27 a foot for .375" diameter rod. Enough for three seals.

If we could find somebody to diamond grind this stuff it
would be a major breakthrough in the cost of ceramic
apex seals. Just like our teflon encapsulated silicon O-rings.

If it worked.

Ianette gets $200 each.

Paul Lamar

Paul,

As a bit of a follow up to this post, I querried a relative who works in
a Michigan shop, as to if he could machine this stuff. His reply is
below:  Do you think Keyocera might be sufficient for our "poor man's
ceramic apex seal"?

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I have not heard of toughened zirconia ceramic, however, we use a ceramic
material called Kyocera (key-oh-sara) for high stress draw die
applications. The advantage of Kyocera is that it can be EDM'd. There is
enough electrical conductivity in it for the EDM to work which is not
normal since nearly all ceramics are perfect insulators. It can also be
worked with diamond tools or diamond paste for polishing.

******************************************************

Dale Smith

I think that is silicon carbide as Kyocera is big on silicon carbide.
I also think that may be the material Ianetti is using.
Widely used in high speed ball bearings.

Paul Lamar
 
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