Ed Huntress wrote:
Right, and now black. The black ceramic knives are sinister looking.
Very cool.

Are you sure they're zirconia? Black is usually aluminum oxide. In
high-performance engineering applications, black may be silicon nitride.

I'll bet they're aluminum oxide (alumina).

--
Ed Huntress

--
Latin: It's not just for geniuses any more.



Nope, It is Zirconium Carbide.
They press the blades from Zirconium Oxide powder, Then they fire them
at 14-1500 degrees for a few hours. These blades will be white at this
time,if you wanted a white ceramic this is what you would get. If you
wanted a black blade they run it through a second process called hot
isostatic pressing. During this process the zirconium oxide changes to
zirconium carbide, and you now have a black blade. The trade off it that
the black blades are a bit stronger than the white ones BUT they don't
hold an edge as long.

--
Steve W.


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