Ceramic knives are the latest addition to the various kinds of kitchen knives that are available in the market. These knives are made of ceramic because it is stronger than steel and lasts longer than steel.
They are also very light in weight that makes them easy to handle. Some of the ceramic knives are so sharp that they can be used for any purpose in the kitchen.
But these knives need to be sharpened regularly, just like the other kinds of knives.
What Is A Ceramic Knife?
A ceramic knife is a knife designed with a ceramic blade typically made from zirconium dioxide (ZrO2; also known as zirconia).
These knife blades are usually produced through the dry-pressing and firing of powdered zirconia using solid-state sintering. It is 8.5 on the Mohs scale of mineral hardness, compared to 4.5 for normal steel and 7.5 to 8 for hardened steel and 10 for diamond.
The resultant blade has a hard edge that stays sharper for longer when compared to conventional steel knives. While the edge is harder than a steel knife, it is more brittle.
The ceramic blade is sharpened by grinding the edges with a diamond-dust-coated grinding wheel.
How to Sharpen Ceramic Blade Knives
A while back, I received a question that asked about the best way to sharpen stainless steel knives, a common problem, especially considering how much easier it is to sharpen carbon steel than stainless steel. Well, it seems a lot of you benefited from that article, and as a result, I thought it’d be a good idea to do a very similar article detailing how one can sharpen ceramic blade knives, since those are even more tricky to sharpen.
Ceramic is basically the black sheep material of the cutlery industry, and whilst many do like using it in the kitchen, I’m not personally all that fond of it myself. If you haven’t jumped the gun and purchased some ceramic knives yet, but are considering it, I’d suggest against it.
That discusses the pros and cons of using a ceramic blade knife over a steel blade knife.
Do Ceramic Knives Get Dull?
Over the past few years we have been swamped with advertising that equates ceramic as the viable alternative to steel, especially for kitchen knives.
Ceramic has been promoted with the incredibly silly marketing promise that it never gets dull: obviously we know this is nonsense.
Ceramic (as used in cutlery) is primarily made of Zirconia (zirconium dioxide), which, while it does have some advantages, is by no means a wonder material – a fact anyone who has used ceramic knives firsthand knows.
Is It Tricky To Sharpen A Ceramic Knifes?
The main crux of the problem is that, while ceramic looks and feels great, it’s also incredibly brittle, and thus much easier to break than any steel knife you could imagine.
With that in mind, when it comes to sharpening a ceramic knife, you absolutely must keep in mind that under no circumstances should you exert too much pressure on the blade laterally. Or it will literally snap in half.
I’ll explain this in further detail below, but it’s the one rule to sharpening ceramic you’ll need to remember.
For those who have sharpened blades besides those made of ceramic, you need to keep this rule in mind particularly because you’ll likely be looking for some kind of spring or feedback – like with all the steel knives you’ve sharpened in the past. Ceramic does not give when pressure is applied, much like glass, so don’t expect any level of spring or feedback with these, period.
Also, when sharpening ceramic, unlike sharpening steel no burr will be formed because ceramic is not a ductile material. As a result, edge sharpness will ultimately be dependent on the final grit of the edge and how precise your movements are.
How Can You Sharpen Ceramic Knives?
1.Electric Knife Sharpener
You can invest in an electric knife sharpener as this is one tool that you can use in sharpening your ceramic knives. I suggest that you look for one’s that diamond abrasive as it can remove nicks easily.
However, there are only a handful of electric knife sharpeners good enough to sharpen ceramic knives. I have the Kyocerca Advanced Ceramic Electric Diamond Knife Sharpener at home, and so far, it has done a good job of sharpening both ceramic and steel knives. This is a battery powered device which features a diamond grinding stone capable of removing up to 0.5-millimeter nicks.
I suggest you wear cut-resistant gloves in using an electric knife sharpener. Hold the sharpener down with one hand, while holding the ceramic knife in the other hand. Slowly pull both sides of the knife against the grindstone.
You can then check the sharpness of the ceramic knife by cutting a piece of paper. The blade is already sharp if the knife easily and swiftly cuts the paper. If not, then you need to continue passing the blade into the slot.
In my experience, 4-5 passes are enough to sharpen the blade. You might need more passes if the blade has become dull.
Sharpening rods aren’t as convenient as electric knife sharpeners, but these can also be effective in sharpening a ceramic knife. Look for one made of diamond steel such as this one.
How do you sharpen ceramic knives with a sharpening rod? It’s pretty simple. While holding the sharpening rod vertically or horizontally, strike the blade against the rod about three times at each side. That’s it!
Again, remember to wear cut-resistant gloves when sharpening ceramic knives with a sharpening rod. Wipe the blade with a towel to prevent leaving behind metal fillings.
3.Using Work Sharp Knife And Tool Sharpener
If you have many ceramic knives, then I suggest that you invest in a work sharp knife and tool sharpener. The BOKER 09DX003 Work Sharp Knife & Tool Sharpener is not exactly cheap, but it is a good tool to have if you have multiple ceramic knives. You can also use it in sharpening other knives, and not just ceramic ones.
This tool may look intimidating and complicated to use. But I assure you that you won’t have a hard time using it.
Here’s how you sharpen ceramic knives with this tool. Lay a towel on an even surface and then place the clean tool sharpener. Insert the grit abrasive belt as well as the outdoor knife guide into the work sharp knife and tool sharpener.
Hold the tool by one hand. Using your other hand, slide the blade 5-6 times at both sides. After that, change the abrasive belt with a higher grit. Continue to slide the blade from left to right until you feel sharpness coming out.
Use a piece of paper to check on the sharpness of the blade. Then wipe the blade cleanly with a towel to get rid of metallic particles.
Manual Sharpening Steps
- Apply water to the knife sharpener.
- Place the knife sharpener flat on a non-slip surface.
- Hold the knife in two hands, one on the grip and the other holding the back of the blade with the sharp edge facing away from you.
- Gently place the knife’s edge onto the stone at the appropriate angle, close to the handle.
- DO NOT APPLY ANY DOWNWARD PRESSURE!
- Check that you are not pushing down on the stone at all!
- Push the knife forward, away from you, sliding from the hilt toward the tip so the entire edge slides along the stone.
- Lift the knife from the sharpener.
- Place the blade back down into the starting position.
- Repeat until you’ve swiped six times.
- Turn the blade over and repeat on the other side six more times.
How To Maintain Ceramic Knives
Due to the brittleness of the ceramic blade, there are specific care and maintenance issues you should be aware of to keep you knives in tip top shape.
- Never use a glass cutting board. Instead, always use a wooden or plastic cutting board.
- Hand wash your knives.
- Never toss a knife in the sink, as this can easily chip the blade. Likewise, dropping a ceramic knife can cause considerable damage.
- Don’t use ceramic knives to cut through tough, thick, or frozen foods.
- Store them carefully. The blade shouldn’t come in contact with other utensils. It’s best to store ceramic knives in a protective sleeve.
Ceramic knives may take a while to go dull but you’ll eventually need to sharpen them in the future.
I suggest you invest in an electric knife sharpener or a sharpening rod as these tools are effective in sharpening ceramic knives.
A work sharp knife and tool sharpener, on the other hand, is best suited for people who own multiple ceramic knives.
I believe you won’t encounter any problems in using any of these tools as long as you follow the pointers I discussed above.