Ceramic knives are made from zirconium oxide--zirconia for short. The material is stronger than steel. A diamond-coated sharpening wheel is needed to sharpen the knife, because it is the only sharpener stronger than the ceramic. To make your own ceramic knife, you need the sharpening wheel, a molding press and a high temperature kiln. If you do not own these items, you can rent them at some home improvement stores or use them at some high-end ceramic shops.
Purchase a package of zirconia powder, which is available at ceramic shops. Pour the powder into the knife mold. Fill the powder to the top of the mold.
Set the kiln temperature to 2,552 degrees Fahrenheit. If you're doing the project at a pottery club, ask an employee to set the temperature for you.
Insert the mold into the press. Turn the dial to 10,000 psi, or adjust the electronic range to 10,000 psi. Pull the handle or push "start" to apply pressure to the mold. Remove the mold from the press. Using your hands, remove the knife from the mold.
Place the knife into the kiln. Leave it there to fire for about 48 hours. Remove the knife from the kiln and allow the knife to cool completely.
Sharpen the blade of the knife with the sharpening wheel, beginning on one side. Use a sweeping motion across the wheel, starting at the tip of the knife and alternating sides after each passing.
Kilns can reach the set temperatures within 20 minutes, depending on the brand. Many have external temperature displays.
Many ceramic shops have molding presses, because they provide molding services as well.
After you sharpen the knife, you can apply a handle to the base. This can be wood, metal or plastic.