AUS8/8Cr13MoV/13C26

[Thomas W]

At 60 Rc it has perfectly good wear resistance with greater toughness than the super stainlesses, along with being easier to sharpen and more corrosion resistant.

Larrin, this is interesting, could you elaborate on the higher hardness/corrosion resistance relationship?

StJames are you bucking for that Ti/ZDP Cyclone test sample?

 

[hardheart]

Cost is a factor Larrin, but we are having complaints with 13C26 developing "spots", and corrrosion is just not acceptable to a gang of our customers. So...we are giving 12C27 a shot. Thoughts?

Benchmade and Queen do well with consumers with their D2 in folders. 154CM and ATS34 aren't really that high on corrosion resistance and were pretty much considered standard for years.

 

[stjames]

StJames are you bucking for that Ti/ZDP Cyclone test sample?

Only every chance I get

 

[Cliff Stamp]

I did find the choice for the Outcast to be strange ...

It fits in with the general perception of steels which is quite ingrained. As Thomas noted, if lots of people do it and we sell a lot of it, then it must be right. Consider the promotion of forging from many makers who sell a lot of blades and then read the following :

http://www.cashenblades.com/articles/lowdown/lowdown.html

Popularity is one thing, actual factual performance is another and the two are not 1:1 correlated. The first thing that has to be eliminated is that there is such a thing as a "superior" steel. These are just manufacturing phrases designed to sell products.

Steels have physical characteristics, L6 for most people would be a superior steel to M2 for a chopping knife, M2 would be superior for most people to L6 for a meat cutting knife. Saying one steel is "superior" is like saying one type of knife is superior. Is a paring knife superior to a fillet knife? What do you want to do. The same goes for steels.

They could do carbon steels cheaply as well, but then someone shopping for cheaper knives probably isn't interested in putting in extra effort to prevent corrosion.

Those knives were traditionally carbon steels, a lot of them still are plus look at the price of the Byrds. Those knives are not overly cheap either, MSRP of $85. I like the looks of some of them and really need to get a couple of decent slip joints, ideally with deep hollow grinds.

Spyderco produces a lot of different models, but then they have a laundry list of discontinued ones almost annually.

Yeah they also introduce new models consistently as well and that is one of the consequences. They also change and upgrade in response to user feedback.

I'm not sure what slip joints you are referring to, we don't make any.

Sorry, I assumed this was a slip joint :

http://www.kershawknives.com/knivesTools/images/doubleDutyRO.jpg

-Cliff

 

[Thomas W]

As Thomas noted, if lots of people do it and we sell a lot of it, then it must be right.

I don't recall noting that Cliff, hopefully I didn't infer it.

Success can be measured differently by individuals and manufacturers alike. Cliff, I would hope you wouldn’t lump Kershaw as one of those followers within the industry, uncaring, and unwilling to go the extra mile in blazing the trail it takes to go from concept to a finished product. Unlike some others, and despite what you seemingly think, we do care what goes into your all’s pockets, and work hard and spend loads of money to ensure that happens. We also back up our work for a lifetime. Ken Onion isn’t a follower, never will be, and I also know Grant and Gavin Hawk pave their own wild path, and always will.

We are getting there Cliff, someday maybe even in your world we will get there. Just know we won’t always make the decisions you think are best.

 

[The Mastiff]

Thomas, I think you show a lot of class in not passing the buck in situations where descisions were made before your tenure. No excuses to be found in your responses.

I'll try to find the thread sometime but a company officer from SOG tried to tell us that misrepresenting the steel in knives the company had been doing was doing us ELU's a favor.

No BS from you. Don't allow the pain in the ass moments to change you.

Cliff, I have a lot of respect for your knowledge. It greatly exceeds mine. In this case I'd think a more appropriate response would be to acknowledge the recent movement towards quality shown by the company, not focus on old decisions. Look rather at the direction Kershaw is taking. Regards, Joe L.

 

[3Guardsmen]

Thomas & Cliff,
You are two people I really respect on these forums! I see Kershaw as a company on the rise. Where other, formerly well respected companies are taking the low road these days, and copying others, Kershaw and Spyderco are making leaps and bounds in the industry, and doing it honestly! Here are some examples, IMHO, of Kershaw's strides:

The SpyKer: The first dual-production company collaboration I can remember, and IMHO, a well deserved slap in the face to a well known company that tried to roll over patents and trademarks held by others. I say, bravo!:thumbup:
The Spec-Bump: The first production use of CPM-154, grooved G10 handles, and the hidden blade stop. A huge success!:thumbup:
The Offset: The first production use of an M.I.M. (with H.I.P.) blade. Awesome!:thumbup:
The E.T.: Taking an original and very complex custom design and translating it into one heck of a well made, lower cost production piece, affordable to the average person. Fantastic!:thumbup:
The G10/S30V Leeks (2 variations) & the Ti/ZDP Leek: Taking a very functional design and spicing it up for the "knife/steel-nuts". Outstanding!:thumbup:
The "Zero Tolerance" line: Making high quality, custom designed knives available at a lower price-point, and doing it while giving back to our wounded warriors (paralyzed veterans). I applaud you!:thumbup:

In my opinion, Kershaw is really taking it to the next level! Though they may run their 13C26 1 RC point lower than what some consider optimal, I'll still buy them. I think it is fairly easy to assume that if the demand is there for a harder run 13C26, Kershaw would be just the company to do it.:thumbup:

Thomas,
Cliff is a very well informed, detail-oriented knife enthusiast, and he is not affraid to ask the tough questions, which is why I respect him. I am glad someone as knowlegable as he is posts here to help assist with the flow of information. I am also glad you are here to do the same. Keep up the great work!

Regards,
3G

 

[3Guardsmen]

I didn't mean to take your thread, a very good one I might add, off topic.

Regards,
3G

 

[hardheart]

It's fine by me. As Thomas pointed out, Kershaw's about the only game in town for production folders in one of the steels I asked about. Talking about things like why that steel, that hardness, and general design philosophy is cool.

Though, it will be nice whewn Larrin responds to Thomas about the properties of 13C26. Though I believe he and Cliff may have pointed it out before. 13C26/AEB-L has a specific ratio and quantity of carbon and chromium, which leads to very small, very hard carbides and a sufficient level of free chromium to resist corrosion when heat treated properly. At least I think that's right

 

[Larrin]

Larrin, this is interesting, could you elaborate on the higher hardness/corrosion resistance relationship?

I simply added as an afterthought that it has good corrosion resistance, though you bring up a good point. As the austenitizing temperature increases, so does the hardness, this is because more of the carbides are dissolving in the matrix, so more carbon and chromium dissolve in to the matrix. So as austenitizing tmperature increases, so does corrosion resistance. On the other side, as the temperature goes down, carbide volume goes up, and to a certain point, so does toughness due to less carbon, though you can still get the same hardness from a lower temper. However, that certain point where toughness starts to decline is reached when the lower temper to reach the same hardness as a heat treatment at a higher austenitizing temperature is no longer high enough to gain toughness from the lower austenitizing temperature. You have to test to find out what the best combination of properties is for your application.

Really, I can't understand why they are getting "spots". 13C26 should have more chromium in the matrix after heat treating than 154CM or S30V, though both of those steels have molybdenum. I've only seen one thread on the forums about getting spots of corrosion. Are there more complaints than just that one? We've made thousands of bars of AEB-L damascus, and we've converted several custom makers to AEB-L, and none of us have had complaints of corrosion; however, maybe all of these knives I mentioned are at least fairly high end, they might be babied. Needless to say, people would not be happy if their stainless damascus was rusting. How are you heat treating your 13C26?

And of course, 12C27 should have even more chromium in the matrix than 13C26. I like 12C27, but it doesn't get quite as hard, though pretty close, and 13C26 has as much as 44% more carbide volume for greater wear resistance. It may be a good upgrade for knives that were previously 440A.

 

[nygiantsfan3342]

Cliff, I have a lot of respect for your knowledge. It greatly exceeds mine. In this case I'd think a more appropriate response would be to acknowledge the recent movement towards quality shown by the company, not focus on old decisions. Look rather at the direction Kershaw is taking. Regards, Joe L.

I agree mastiff.

I have only been a knife collector for six months, but my first real knife was a Kershaw Leek I bought at Wal-Mart and I've been hooked on Kershaw ever since. What Kershaw did in the past doesn't matter to me; only what they do in the present and future. When I compare Spyderco, Benchmade, and Kershaw, I choose Kershaw! I have spent over $2,000 on knives in 6 months and none of my knives cost over $300. So maybe I don't know everything about knives like Cliff or Thomas, but I do know what I LIKE. And no offense to any knife Snobs out there, but I am the target customer for Spy, BM, and Kershaw. NOT the discriminating knife connoisseur who spends $2000 on one knife. I am the customer who wants to USE the knife and yes I do like to show it off to my friends, especially the SpeedSafe! I look forward to the bright future of Kershaw as long as its in the hands of Thomas W.

Jeremy

p.s. I had to look up the spelling of Connoisseur

 

[gunmike1]

I have some CRKT's in AUS-8A and a G-10 Cara Cara in 8Cr13MoV. The Cara Cara seems to have slightly better edge retention and burrs less, so sharpening is easier. I think CRKT runs their stuff pretty soft, so Benchmade's AUS-8A may well outperform the Cara Cara, but I don't know. I think either steels make a good EDC steel, as long as you aren't planning to tons on tough cutting with them.

 

[Cliff Stamp]

I don't recall noting that Cliff, hopefully I didn't infer it.

What was the above supposed to mean then exactly :

Until then we will continue to manufacture under achieving knives that somehow continue to sell (some even in volume) to unsuspecting, unknowledgeable, and unknowing buyers (some of whom even roam the halls of BF’s).

Thomas as I have noted before, I don't in general "like steels". I in fact carry knives which are just marked "stainless china" I assume these are AISI 420 or an equilavent. They work perfectly fine as a precision cutting knife that gets rare use and looks harmless. The one I am EDC'ing now has a picture of the statue of liberty on the front (I am canadian) so it also looks kind of silly, which is what I want because I often use it in places not friendly to knives.

Plus if I am at a friends house and they are cooking dinner and I help by peeling some vegetables and I take out the chinese/EDC then it is very impressive. It is reground, very sharp, opens/closes easily with one hand, and has no ergonomic isses and is best of all dirt cheap. If I did the same thing with a Sebenza it just looks absurd because you could buy a used car for the same price. My friends are tradesmen and similar so it would be seen as a silly thing like getting your teeth gold plated. Not a lot of fisherman/carpenters tend to do that with their extra money.

If you define a type of knife and a specific purpose and a heat treatment for a steel I could tell you if I liked it for that role. As I have noted, there is no such think as a superior steel, they all have their properties and their uses. Now you can get superior manufacturing processes, but even then you can't blankly use this to label steels. P/M A11 (10V) isn't directly superior to ingot L6 for example. They are different steels intended for different tasks.

I'll try to find the thread sometime but a company officer from SOG tried to tell us that misrepresenting the steel in knives the company had been doing was doing us ELU's a favor.

Ron Anderson acting as SOG's rep.

13C26/AEB-L has a specific ratio and quantity of carbon and chromium, which leads to very small, very hard carbides and a sufficient level of free chromium to resist corrosion when heat treated properly.

Exactly right.

I simply added as an afterthought that it has good corrosion resistance, though you bring up a good point.

You need to put this in perspective, the corrosion resistance is lower than most cutlery stainless steels.

Really, I can't understand why they are getting "spots". 13C26 should have more chromium in the matrix after heat treating than 154CM or S30V, though both of those steels have molybdenum.

You can't compare corrosion resistance on that basis. It is better than just looking at the raw chromium percentage which a lot of people do but it still ignores way too many factors. The first thing you have to do is take into account the carbide fraction. If for example 50% of the steel is carbide and the steel has 8% of the origonal chromium dissolved, then the actual ferrite can end up with effectively 16% chromium dissolved in it. You have to be careful here because compositions are by weight and carbide levels are usually given on volume so you have to adjust for density.

So not only does 440C have more chromium dissolved in the austenite, the amount of steel which is actually austentite isn't 100% because there is a significant amount of primary carbides. AEB-L can be soaked so it has no primary carbides and just a small amount of sub micron secondary carbides which only take up a very small volume (about 5% according to Sandvik and I would assume this is effect by soak temperature). Thus when comparing it to 440C it gets hit three times, less total chroimum dissolved, a far lower carbide adjustment factor and no moly. You also have to be very careful when talking about carbides, secondary and primary carbides should never be intermixed, they have quite different properties in steels.

On top of this is how they are heat treated. When the steel is quenched the chromium dissolved in the austenite is meta-stable. As it is air cooling it passes through temperatures at which it has the required energy to precipitate out of the steel and it will do so readily. This is why oil quenching gives better corrosion resistance. It also gives better toughness because these precipitates tend to weaken grain boundries.

If you are getting lower corrosion resistance in AEB-L/13C26 than you need, raise the austenization point, the upper level is quite high for that steel, quench in oil, do a deep cold treatment and temper low. This will also raise the hardness to near maximum and provide optimal edge stability, push cutting sharpness and fine edge retention. If this doesn't have the required toughness, or still lacks in corrosion resistance then drop down to 12C27. If the same thing happens drop back to 12C27m. I don't think I have ever read anyone complain about corrosion resistance in 12C27m, it would take pretty severe enviroments and in such cases you are likely looking at H1 or similar steels.

-Cliff

 

[Larrin]

You need to put this in perspective, the corrosion resistance is lower than most cutlery stainless steels.

You're right in the fact that most cutlery stainless steels are 420 or 440A. AEB-L has greater corrosion resistance than 154CM, it just has way more chromium in the matrix. I have seen "spots" of corrosion on our 154CM kitchen knives, and I've never seen them on our AEB-L kitchen knife. The 154CM blades were heat treated both with the upper temper and with lower temper, depending on the knife.

Edit: Were the 13C26 knives with spots sporting a bead blasted finish?

 

[Thomas W]

Quote:
Originally Posted by Thomas W
I don't recall noting that Cliff, hopefully I didn't infer it.

What was the above supposed to mean then exactly :

Quote:
Originally Posted by Thomas W
Until then we will continue to manufacture under achieving knives that somehow continue to sell (some even in volume) to unsuspecting, unknowledgeable, and unknowing buyers (some of whom even roam the halls of BF’s).

Cliff, I guess you missed this part at the end of my post;

Is it ok for me to be a little sarcastic everyone, just this once?

Were the 13C26 knives with spots sporting a bead blasted finish?

Sorry should have mentioned that Larrin, the knives were indeed bead blasted, which I am sure assisted in the issues.

 

[hardheart]

My Vapor II developed rust spots quickly, I just attributed it to the finish. It seemed like a very fine media blast, is that the same finish on the other knives?

 

[Cliff Stamp]

You're right in the fact that most cutlery stainless steels are 420 or 440A.

I wasn't being so exclusive, 440C is also far more corrosion resistant. However you need the upper austenizating range to get optimal corrosion resistance and oil+cold.

AEB-L has greater corrosion resistance than 154CM, it just has way more chromium in the matrix.

I discussed this with Crucible awhile back as I was curious as how 154CM could be stainless with 18% chromium carbides. Problems come from mixups in what is said and what is actually meant because of intermixing volume/mass percentages and not including the effect of carbide/austenite volume fractions.

Take 154CM, assume it has 11% of chromium in the austenite. This means that 35% of the total chroimum is available for the primary carbides. Considering the chromium carbides are actually a mix of chromium, moly and iron carbide, this 5% chromium (by mass) can sustain that large a fraction (by volume) of primary carbide. This was according to Ed Tarney.

There are other complications as well such as elements like nitrogen which increase corrosion resistance as long as you temper low, and solid solution elements like cobalt which will indirectly increase corrosion resistance (minor) as they again will decrease the basic amount of actual ferrite in the steel.

I'd be interested to see Q-fog data on the sandvik steels, Spyderco is talking about a Bushcrafter and those steels are ideal for that so hopefully we get some materials data and maybe he will do a high hardness 13C26 Calypso Jr. run (or similar) as well.

I guess you missed this part at the end of my post

No I read it and sarcasm means your statement is inverted not that it is meaningless. So for example if I said "Yeah, and when you order your Strider knife be sure to tell Mick you are giving it to me for a test drive as we are close friends and you respect what I have to say. Mick is always interested in my comments about his knives." Most people would realize this is sarcasm as the opposite is true.

-Cliff

 

[M Wadel]

the uddeholm marss500 and sandvik 12c27modified is the same steel by different companies (i think uddeholm has discontinued theirs tho). these steels are probably some the toughest staniless steels, + they have very high corrosionresistance. usually used in kitchenknives in sweden. very easy to sharpen, i have many knives with this steel.

12c27 (erasteel also makes their own version of this, PMC27, used in damasteel) is the allrounder, i think the max hardness is 60.5 w cryo (@ 2010F and 1x2h tempering @ 345F, with 15min -140F cryo after hardening and 15min after tempering)

AEB-L/13c26 gets even harder, i think 64max maybe a little less but isnt as "stainless" as 12c27 or marss/12c27m.

the really good thing with these steels is they are cheap around 10€/kg for AEB-L and thats 1/4 of RWL so its a good deal imo

 

[Thomas W]

And a follow up right hand as well Cliff. My, my, my, who new you were the aggressive type, even to those in the same league.

Cliff I have no beef with you, we just see things from a different perspective. I won't go into what it takes to run a successful knife company in this day of age Cliff. Believe me, it's not easy. I know that is not your objective or specialty, but it is mine.
All that working within tricky financial parameters, R&D, manufacturing, predicting markets, new products, material issues, legal battles, maintaining a staff, payroll, insurance, royalties, marketing, getting placement, selling, warranty...... gosh did I miss anything? Oh yea, keeping everybody satisfied. You make it sound like we are cutting corners Cliff, and that bothers me...a bunch. Sorry we don't live up to higher expectations Cliff. Kai Corp is unique it how it conducts business Cliff, sorry I won't go into the details. As I mentioned before we all measure success differently.

Cliff, we work hard, do our own thing, are certainly not "me too", and are successful. Kershaw has an innovative stable, led by one Ken Onion. Most folks get a warm fuzzy feeling when Ken is mentioned. He is respected within the industry, and we take advice from him. I feel it is great advice. We have long standing relationships with many makers, manufacturers, and vendors. We even staff a talented maker in our R&D dept. We are now doing a knife with RJ Martin, again who has the respect of his peers.
We use steel you approve of, and some you don't. Same goes for our patterns. There are times we even make price point knives. We utilize a variety of locks, as well as steels, we push technology, but none of that seems to impress you Cliff, but I have come to feel that’s ok. Cliff under the restrictions that are placed on us manufacturers, we will never make the perfect knife in your eyes everytime, it just won't ever happen. Don't slap us for that.

Now what I won't do Cliff is take swings at you, although I can't say the same for you. If it is the last word that is important to you, it's all you Cliff. I'm not here to argue with you. Spirited debate, no problem. If you feel it necessary to take shots at us, I'll just have to take the high road with you. FYI, I won't take a sarcastic tone with you again.
I actually am fascinated with your posts, although you argue a bit much for my personal taste. Keep up the fine work Cliff, but look to stay close to what you know best.

 

[hardheart]

Well, I don't know if I've ever felt this slighted as a customer before. Kershaw doesn't make knives just for Cliff, so Kershaw shouldn't be concerned just about Cliff's comments, complain about any attacks by Cliff (especially when there weren't any), or try to justify the business practice of a sizable corporation to one man. It is ceratainly most distasteful when a person becomes so preoccupied and defensive about Cliff's comments.

Everyone knows Cliff is the 'aggressive' type. The high road would have been to keep quiet. Now I need to check out Stapel's site again for his little AEB-L fixed blade.