Ceramics for knives

Anyone know what ceramic is usually used for ceramic knives?

Also: anyone know a good source for small amounts (IE prototype amounts, not full production run amounts) or full-Yttria stablilized Zirconia?

get this book its the don

Kyocera, the top knife ceramic knife manufacturer makes it’s knives out of a sintered Zirconium Oxide (also called Zircon, or Zirconia). Here’s a description of the sintering process:

http://www.mtm.kuleuven.ac.be/Research/C2/Processing%20of%20ceramic%20materials%20Sintering.htm

Their lower-end blades are made in a standard sintering process, While the Kyotop blades undergo a hot isostatic pressing process which improves the toughness of the blade. This page describes the HIP process:

http://www.dynacer.com/HotIsostaticPressing.htm

Some lower quality off-brand ceramic knives are made of sintered Aluminum Oxide (also called Alumina). When I say lower quality, remember that any ceramic knife can be made much sharper than a steel one, and the blade will last longer. But Zircon is seen as a better material, since it is harder than Alumina, and therefore will hold an edge longer.

The Lefteri Book is awesome, and a good start.

http://www.amazon.com/exec/obidos/ASIN/2880466687/idfuel-20

But, if you want a much more in-depth knowledge of actuall manufacturing processes, take a look at Modern Ceramic Engineering: Properties, Processing, and Use in Design

http://www.amazon.com/exec/obidos/ASIN/0824786343/idfuel-20

Unfortunately, like all engineering manuals, it costs more than I make in a month :slight_smile:

thanks a ton guys, picked up the first book mentioned, and looked at some sintering web sites…

seems like it’s probably too involved for a small production-run anyway, so I’ll be waiting a while.

anyone know any way to get small machinable blocks of either full-ytt stabilized Zirconium (my preference, for strength and durability) or Alumina (for ease-of-procurment…)?

Sorry, I forgot to specify, by workable I mean that I could diamond-grind, not the conventional-machine workable stuff they have that isn’t as hard, I’m going to be making knives, so I need the full-on hard stuff.

You might also want to check out a manufacturer named Boker. I have several of their knives and they are fantastic. I have no idea what the actual composition is, but it’s not the white stuff you see on kitchen knives…which I assume is a more basic ceramic.

Boker’s amazing black ceramic knives are hot isostatic pressed ceramic. This process causes reduction of the ceramic body, and changes the color from light to very dark, while increasing the extent of sintering, and therefore, hardness, of the blade. Boker also makes kitchen and utility knives in the standard white alumina at a lower cost.