The future is now: Ceramic Knives!

[SpyderEdgeForever]

Ceramic knives have been discussed before but let's examine them more.

It really is truly amazing. Ceramic blades that are in the shapes of what were once only steel blades.

Look at this from Rapala, the world famous maker of fishing lures and tools:

https://www.rapala.com/rapala/knives/ut ... ic&start=2

A ceramic fishing utility knife with a robust 4 inch ceramic blade. What great design features. And the inexpensive cost. That is so cool.

What do you all think of such a knife?

If you were to talk about ceramic knives on blades even in the 1990s, most people would think you were talking far future Star Trek Star Wars science fiction type things. Now they are available and mass-produced for people.

I know, I know, someone is going to bring up issues like brittleness or "what do you sharpen it with?" and all of that. But the facts stand: Ceramic is superior to steel, to iron, and, you can always use diamond and other ultra hard sharpening devices.

And eventually the brittleness will be overcome with bendable ceramics that have the hardness of ceramic with the fracture toughness of steel.

[MichaelScott]

I’m old school. I like steel.

[The Mastiff]

There were ceramic knives in the 90's. I had a couple and was unimpressed. I'm with Michael Scott on wanting steel on my knives. I've tried all the substitutes that were available to me including Ceramic, Titanium, Cobalt alloys, tungsten grit and even various reinforced plastics and stone like obsidian. Nothing replaces steel yet.

Joe

[Evil D]

"Ceramic is superior to steel"

Let's first define exactly how it's superior, because it's extremely inferior when it comes to toughness for example.

[knivesandbooks]

I agree with Evil D. You can't just he throwing out these statements. "Ceramic is superior to steel". Idk how this could possibly be true. And I'm not holding my breath on future tech.

[bearfacedkiller]

Seeing as how most people lack the skill or desire to sharpen their knives I think ceramic knives certainly do have a widespread application. Kyocera ceramic kitchen knives are very affordable and they offer lifetime sharpening which shouldn’t be needed very often.

Steel is better in quite a few ways for me but for the masses ceramic offers another option.

[SpyderEdgeForever]

Good points.

Darby, what them ceramic makers need to do is make a ceramic knife as robust and durable as the Varuseleka Puukkos you and I love, right? Both the carbon and stainless steel they use have a thick cross-section and are razor-sharp. Man that is great steel.

[MasterChiefPink]

Not all ceramics are created equal.

That Rapala knife is a cheap Chinese ceramic that isn't strong. Like the Boker ceramics of yesteryear, they are brittle and fail for lack of bond (sinter) strength.

The color only tells you carbon was or wasn't added to make it black.

There are only two sources of high quality Japanese made ceramic knives: Kyocera and Dalstrong (also sold as Wilson now).

For the white ceramic there is an easy test that shows you how well it was sintered. Put it up to a light and put your finger behind the blade, blocking the light. Cheap ceramic doesn't let the light through. Kyocera knives you can see your finger through the blade. Like gems, the higher the quality, the clearer the ceramic.

For the amount of time and energy that goes into making Zirconia into a blade, what you pay for a Kyocera knife is very reasonable! Dalstrong knives are still under review, but looking good.

When it comes to grades, there are essentially 3, with a .5 kinda. White would be standard grade, and cheap black blades are just added carbon to standard grade. Kyocera black blades are an improved HIP blade that gets you longer life, Kyotop blades are the ".5", because fire the ceramic a second time to improve the bond (call those high grade). Both of those are Z206. Then there is "hyper ceramic", Z212. This uses a cold press (CIP) at ridiculously high pressure, and a higher temp.

It's more complicated than that but not necessary to get into all that. I still prefer the cleanliness of the white, as the edge does seem to get a touch sharper. I can easily shave hair with my white ceramic Kyocera knife. And Ken Swartz sharpened white will blow your mind how sharp it gets!

Also, older and low quality ceramics cannot hold more than about 45 degree inclusive edge. Just to weak/brittle. The Dalstrong convex edges are already down to 30. It makes a world of difference. Oh, and the thin blades of Kyocera and Dalstrong, possible only because of their quality sintering, are a huge improvement over the rest.

[JD Spydo]

There were ceramic knives in the 90's. I had a couple and was unimpressed. I'm with Michael Scott on wanting steel on my knives. I've tried all the substitutes that were available to me including Ceramic, Titanium, Cobalt alloys, tungsten grit and even various reinforced plastics and stone like obsidian. Nothing replaces steel yet.

Up to this time period and with the present technologies where they are I'm with "The Mastiff" and other guys who voted for knives made with steel. I've owned ceramic knives and ones that were rated as good quality too. I've also owned a couple of knives made with other exotic materials like "CERMET" and again I wasn't all that impressed.

Now I will say this that ceramic has indeed progressed a lot in the past 20 years and Spyderco's ceramic sharpening stones which are made with so called space age ceramics are among my favorites sharpening stones. Albeit I haven't used a ceramic blade that has proven to be superior as of yet. I still say that ceramic technology has a long way to go to replace knives made with premium quality steel alloys.

Also you want to consider that vast progress has also been made with steel knives in the past 15 years in particular. There are better heat treatments, better ways of quenching and just better steel alloys all together. It hasn't been all that long ago that stainless blades were looked down upon>> and we all know how that sector of the market has vastly improved. So with that being said I guess time will tell if ceramic will surpass steel knife blades. But for right now I don't plan on getting rid of any of my premium quality steel knives ( stainless or high carbon).

[Evil D]

I would imagine that someday what ceramic really has to offer is potentially a "self sharpening" material, maybe similar to sea urchin teeth (if you don't know about sea urchin teeth, look that up). Otherwise there really are few things that steel can't already do for knife applications that a ceramic could offer, if not do better.

[The Deacon]

I'm with Michael and Joe. Ceramic knives have been around for decades and still suffer from the exact same issues they did when first introduced.

[Doc Dan]

I would be all for a ceramic blade if the toughness issue could be worked out. These materials get harder and sharper than steels, in general, and hold edges for a long time.

There are signs that change is coming. Elastic ceramics is one such area: http://science.sciencemag.org/content/341/6153/1505
Here, you can see that they seem to have solved some of the problems associated with martensitic transformation and have developed a less brittle elastic ceramic that can withstand stresses.

[JD Spydo]

It is an interesting topic in spite of the fact that I'm personally not a fan of ceramic knives as we know them at this present time. But I think that for ceramic to be a good option for use in cutlery the material is going to have to conquer a lot of problems you have with the ceramic materials they are presently using. Like some of you have said there is no toughness properties that tend to make a desirable knife blade with ceramics at this time. Also the ceramic knives on the market at this time are very fragile>> I've got a dear lady friend who works in a restaurant kitchen and she has told me how easy it is to destroy a ceramic knife.

Also sharpening ceramic knives is truly a big undertaking>> for those of you who hate to sharpen knives with the steels that they presently make knives with I can tell you that ceramic is 10 times worse to sharpen. And diamond as far as I know is the only abrasive you can use to do it with>> also it takes a special type of diamond grit to do it successfully.

There will be a time when ceramics will progress to the point to where the materials will be much more useful for a wider range of products but that time is way down the road and maybe even decades away.

[MasterChiefPink]

Update: Wilson Revolution ceramic blades, which appear to be the Dalstrong V3 Spectral blades rebranded with black handles.
Cut very well, edge looks like the 30° inclusive they brag about, and durability is good! Not chopping bone but chopping leafy and fibrous veggies is easy. Weight is low, rather handle heavy because the blade is so thin; though that's why it cuts so well.
Sharpness is ok. Cut some hair but not hair popping sharp. Regardless they are micro-toothy and cut very well on pull and push cutting.
Overall they cut well, last a long long time, do not alter taste or brown veggies, and the price is great!!!!!
I have new DMTs coming (had $1000 worth of stones in my manvan when it was burgled). I will post sharpening with the DMT HardCoat 600/1200 with polishing one the 4000 & 8000 8" stones.

Rank on ceramic blades:
#1 Kyocera Kyotop
#2 Kyocera Revolution (low cost white)
#3 Wilson/Dalstrong V or V3 Spectral blades
#4 Kyocera Black Revolution (cut the same a white but cost more...though does last a touch longer)
#6 Wilson Diamond blade. (Highest cost from Wilson, looks great!...cuts like a Wal-Mart $10-20 knife, just lasts a long long time)

[Crux]

I've had a Boker ceramic knife for 15 years or longer.

[supracor]

An enormous number of steels that Spyderco use acts like ceramic.

D2 begins to have some ceramic characteristics, but things like Maxamet, that is used to replace cemented carbides practically have almost the same toughness of modern Cermets while having the half of the wear resistance.
But you have to think that if you are using Maxamet for a certain application your first thought doesn't go to toughness.
Cermet is not a thing, Cermet is a name to design an enormous family of bonded materials that contains Titanium Carbonitrides instead of WC.

Cermets are the forced future of Spyderco, if Sal & Eric want to continue the home tradition of ultrahigh-carbide/ super wear resistant steels.