How are Ceramic Knives Made?

Have you ever wondered how Kyocera ceramic knives are made? It’s actually a straightforward process, you’ll soon get a grasp of the basics.

Ceramic knives are made from zirconium dioxide, often referred to as zirconia. If you like jewelry, then maybe you’ve heard of cubic zirconia. It is a form of zirconia used to make simulated diamonds, which are just as pretty but far cheaper.

Obtaining the raw material

First we need to find a sand rich in zircon. The sand is taken to a refinery, where the zircon is separated. Zircon is not the ceramic we’re looking for, but rather a mineral also known as zirconium silicate. Don’t be confused, zircon and zirconia sound similar but are quite different. To obtain zirconia, an extra process is needed. However, we won’t go into detail because I don’t want to bore you with chemical formulas.

At the ceramic knife factory

Kyocera’s proprietary ceramic material is Zirconia 206. This material in fine powder form is pressed at a very high pressure (close to 300 tons) in a knife-shaped mold. The result is a solid piece, but quite fragile. It must now undergo another process in order to become harder: Being fired in a kiln at high temperatures, much like regular ceramics. This is probably the longest part of the whole process, it takes about 2 days.

Ok, so now we have a very hard material. The problem is that our knife is currently as dull as a spoon. What should we do about it? We need one additional step.

The edge is sharpened using a diamond-coated sharpening wheel. Why does the wheel have to be diamond-coated? Because zirconia is an extremely hard material, having a hardness of 8.2 mohs while diamond has 10 mohs. By the way, steel is rated at 5-6 mohs. This is the reason why you can’t sharpen the ceramic blade as easily, you must have the right sharpener, or send it to Kyocera and they will sharpen it for you.

Thanks to such a high hardness, the resulting knife is very sharp. In addition, the original sharpness will last for as much as 15 times longer than steel knives!

Feel free to watch the video and see the complete process: