I think we put WAY too much emphasis on alloys...

[singularity35]

Um, it's we English Nazis ...

He who , best!

I surrender to the better Nazi.

 

[Joshua J.]

While I'm no professional in any industry that can be named, I have been doing a lot of reading about knives over the past few years. I know a farrier who still believes in metal compaction, because back in the 80's that's what he was taught, at a top tier college.
(that is to say, it's entirely possible to pay a lot of money to be taught incorrectly.)

Remember that powder metallurgy is a game changer, alloys like ZDP-189 and S90V cannot possibly be produced any other way.
Tell me, how much carbon can be put in a cast alloy? Now look at the charts for CPM 15V.

michaelmcgo, I suggest you take a course or two in powder metallurgy, then do some edge retention testing on ZDP-189 and compare that to your best 1095.


The point that the average person should take away from this thread is proper application of a steel type to the task being done. A whittling knife needs hardness, bun not necessarily wear resistance. Lot's of people love 1095 at Rc 65 for this. If you're going to be cutting through cardboard all day, CPM S90V will go two or three times longer than 440C.
Cutting leather, I need two VG-10 knives to do the same amount of work as one ZDP-189 blade, and ZDP-189 is still sharper afterward.

 

[Macchina]

Are you saying the (as I stated in my first reply) that Crucible has been somehow able to fool the steel community in general into buying their CPM steels?

Yes. They are better to knife company in the sense that they are eaier to heat treat. The end user shouldn't notice the difference between cpm154 and 154cm if it's heat treated right. I know a lot of people will disagree with this statement, but this is the way alloys have worked ince they were first discovered: if allowed time, alloys will evenly distribute.

 

[Ankerson]

I think it should come down to what the knife is going to be used for first off.

Also if it's a folder or fixed blade and or a sword.

 

[Broos]

While I generally agree with the sentiment that we tend to overemphasize small differences in edge performance, I also find exotic alloys very desirable and seductive.

If you read my post, you'll notice that I talked about a standard alloy steel (154CM) has to be left in the austenitic phase long enough for the alloys to completely disperse within the steel. When steel is at it's crystalization or austenitic phase, alloys and carbon flow from regions of high concentration to regions of low concentration until the entire steel body is at equilibrium. If you don't let the steel soak for long enough, it won't be at full equilibrium when it is quenched and it will have large formations of alloys.

Where did you see the micrographs? Were they put out by CM by any chance?

I'm no expert, but I can usually find one. Halfway down the linked page is a short and sweet explanation from Mr. Landes on some of the advantages of PM, ending with a couple very concise statements on the topic of whether a heat treat can remove alloy segregation in a ledeburitic steel (you are stating above that it can). 154CM is a ledeburitic steel. And since you are assuming there has been no peer review of CPM's excellent and informative website, he even links to some of his own micrographs of the same % C alloy steel using conventional & PM methods. The difference in alloy segregation is visible.

http://www.hypefreeblades.com/forum/viewtopic.php?f=3&t=107

Hardness may indeed be the major factor in general as to edge retention, but wear resistance also is a factor that grows in proportion to the slice you use during testing.

 

[Alberta Ed]

Great post. Thanks! It may explain why I keep coming back to simple carbon steel blades, although I do appreciate the new super-steels.

 

[Gadgetaholic]

1095 CV doesn't make any sense in metallurgy terms because all 10XX class steels are only iron + carbon. If you add alloys, you get an alloy number (5160).

1095 CroVan is a variant of 1095 steel, very similar to standard 1095 but with a small amount of Chromium and Vanadium added. KA-BAR uses this steel on the Becker knives. It would be only a small amount better than the standard 1095 if both are heat treated well.

 

[THG]

Pretty much sums up how I feel about blade steel choice these days. As long as it's an appropriate steel for the knife and given a good heat treatment I could care less what they call it.

And to think I used to be a steel snob! Gimme 1095, AUS8, 440C, ZDP-189...I really don't care anymore--it's all good!:thumbup:

Same here. I'm actually not too impressed with my ZDP-189 compared to my VG-10. Both are noticeably better than the 420HC I have, but compared to each other, the difference isn't HUGE as we consistently hear in advertising...

 

[axtalan0]

I enjoyed reading your post. It confirms what many of us knife collectors suspect, namely, that the new "super-steels" are not all they are cracked up to be. They may have marginally better qualities in specific attributes (such as edge retention), but to an average knife user, there is probably not much noticeable difference.

I am a firm believer that knife companies, like any other business "sell the sizzle, not the steak." They use the new steels not because they are SO much better, but because they can charge more for it. Its called over-engineering. Best example is computers: the avarage user probably uses about 25% of their computer's functions, but the companies load them up with sofware anyway, so they can charge more.

I am not saying there is no difference in steels, but I agree with the OP that the difference is not as great as the marketing departments would have us believe, nor does it justify the price difference.

I also think that the next real breakthrough in knives will not come from some new super steel, but rather an altogether new material that will be superior to steel in every way. I hope to see that in my lifetime.

 

[mete]

Micrographs of steels are available from many sources , you don't have to rely on the steel maker.

Any college that taught 'compaction' in the '80s was way behind the times !! We knew in the 60s that it was BS.

Powder metals can be used to make real " super steels" .For example the Fallkniven SGPS blades give you hardness AND toughness.

Each alloying element in a steel is there for a specific reason .Elements like vanadium form very wear resistant carbides.A steel containing only iron carbides is not very wear resistant .Chromium carbides are better and vanadium carbides are better yet.

Fortunately we have a choice. Wear resistance, ease of sharpening , cost, etc - pick what suits you.

 

[shunsui]

I am currently toward the end of my engineering degree an have had a few metallurgy classes so already. I am half way through a fairly advanced Metals Selection course and a lot of what we deal with is the molecular makeup of steels.

Just curious, where are you going to school and which type of Engineering degree are you getting ? Are you going to continue with the CAD/CAM stuff or move into something else ?

 

[dano]

Wow, long post. The moral of my story is: If you buy a knife from a reputable company and the steel is in the hardness range you desire: don't fret over what percentage of what alloy is in your steel. Some alloys do funky stuff to steel, and a couple of steels are starting to stand out as being able to be very hard and not quite so brittle, but their reputation has a lot to do with proper heat treat on every sample (you don't see a lot of BudK knives in M4 do you). The classic steels have been around for a while and have had lots of chances to be screwed up in the oven, resulting in scores of negative reviews of perfectly good steels. Don't expect a 55 Rc 420 blade to hold the edge of a 66 Rc ZDP-189 blade, but also don't expect to be able to bend the ZDP-189 blade and not end up with two knives.

You're going to ruin some people's hobby.

It's all, for the most part, mute, as (I've been saying this for a long time) a vast majority of users would not be able to tell the difference in various steels under normal usage.

Overall, the numbers stamped on the blade are nothing more than a selling point (and there have been a few cases where the blade was stamped with an incorrect type...on accident, of course).

 

[The Mastiff]

You're going to ruin some people's hobby.

It's all, for the most part, mute, as (I've been saying this for a long time) a vast majority of users would not be able to tell the difference in various steels under normal usage.

Overall, the numbers stamped on the blade are nothing more than a selling point (and there have been a few cases where the blade was stamped with an incorrect type...on accident, of course).

Are you guys oblivious to the fact that there are in fact quite a few very knowledgeable and experienced knife users who do know the difference, and understand perhaps better than you and michaelmcgo what the uses of these alloys are, and what to expect of them.

I don'r get where you guys are coming from. It's like telling us that we all could get by with one out of a selection of 5 different 1980's chevrolets.

What's your point?

I've been using 1095 and O-1 since the 60's. I know them well and like them. I also like ZDP, CPM M4, Super Gold, Aogami, 20CV, S110V, S125V, Etc., Etc, Etc.

I don't however like 440C, and some others that have been surpassed. The performance is lackluster to me, and I don't like it's grain structure. Whether one admits it or not the powder steel processes have brought us steels that far surpass the old ones, though I do hear the new Carpenter powder steel process has improved 440C's grain structure and helped to lower the brittleness at higher hardnesses we've come to expect.

As far as hardness = brittleness. Have you tried CPM M4 or M2 at Rc 64 on up?

It's not as brittle as ingot 440C is at RC 58-59 in my experience.


Joe

 

[ikiddp9]

I usually don't care much about super steels. For my folders 440C, AUS8A, 12C27, 154CM, D2 are more than enough for most tasks. For my fixed knives 1095, 440C. And blades in these steels costs a lot less money than super steels.
I do prefer stainless blades tough because I live in a warm and humid county and near seashore too!

 

[Gatogordo]

I would suggest that you might consider getting out of that classroom and try using a few knives out in the field and you'll find that there ARE NOTICEABLE AND, in many cases, OBVIOUS differences between knife steels in actual use. Steel makers know it, knife makers know it, and anyone who uses multiple knives very long in the field knows it. Classrooms try to teach you why, they often don't teach you which or how.

 

[Ankerson]

I would suggest that you might consider getting out of that classroom and try using a few knives out in the field and you'll find that there ARE NOTICEABLE AND, in many cases, OBVIOUS differences between knife steels in actual use. Steel makers know it, knife makers know it, and anyone who uses multiple knives very long in the field knows it. Classrooms try to teach you why, they often don't teach you which or how.

It's not that obvious most of the time unless one is 440A and the other is VG-10 cutting cardboard.

There are way too many variables for the ave Joe to really tell the difference.

For what most people really use their knives for they wouldn't know the difference between AUS-8 and CPM-154 unless they were told before hand.

 

[FortyTwoBlades]

I would suggest that you might consider getting out of that classroom and try using a few knives out in the field and you'll find that there ARE NOTICEABLE AND, in many cases, OBVIOUS differences between knife steels in actual use. Steel makers know it, knife makers know it, and anyone who uses multiple knives very long in the field knows it. Classrooms try to teach you why, they often don't teach you which or how.

Also true! While I don't much care what steel is in my knives these days I DO still pay attention to what's in it! It WILL affect how the knife performs in the field and what I can expect out of it! But my mentality is that they're all good and if heat-treated well will do their job nicely.

Out of curiosity...what do you think would happen if you took a super steel like ZDP-189, BG-42, or S90V...and ran it at 52-54 Rockwell? How would it perform differently from a more basic stainless like 420HC, which Condor uses in machetes (other than being more expensive)?

 

[Nebulae]

so why is this alloy different

http://www.crucibleservice.com/eselector/prodbyapp/highspeed/cpm121.html

have you ever seen 1095 at 70.5 Rc

 

[Rafthos]

try using a few knives out in the field and you'll find that there ARE NOTICEABLE AND, in many cases, OBVIOUS differences between knife steels in actual use.

My foster son is in the military. He was cutting rubber weather sealing off an armored vehicle with a Gerber S30V blade and the blade was unusable after just one vehicle. He was not hitting metal, so he says, and the edge was chipped beyond belief. He purchased a Benchmade in 154cm at the PX that night and used it the next day. The Benchmade worked for around 30 vehicles and was still relatively sharp. I am not sure that based on this experience one can state that 154cm is "better" than S30V. I do question Gerber's heat treating on all their steels. I had a buddy who dropped a guardian 18in onto tile and it broke about midway on the blade. I have to agree with all the real experts who say the number one factor in quality of a knife is heat treat, number two is blade geometry and last is blade material.
Obviously a "good" steel must be used but you don't have to have a super steel to have a great knife. I also think there is much hype in the steel marketing industry.

 

[Josh K]

My foster son is in the military. He was cutting rubber weather sealing off an armored vehicle with a Gerber S30V blade and the blade was unusable after just one vehicle. He was not hitting metal, so he says, and the edge was chipped beyond belief. He purchased a Benchmade in 154cm at the PX that night and used it the next day. The Benchmade worked for around 30 vehicles and was still relatively sharp. I am not sure that based on this experience one can state that 154cm is "better" than S30V. I do question Gerber's heat treating on all their steels. I had a buddy who dropped a guardian 18in onto tile and it broke about midway on the blade. I have to agree with all the real experts who say the number one factor in quality of a knife is heat treat, number two is blade geometry and last is blade material.
Obviously a "good" steel must be used but you don't have to have a super steel to have a great knife. I also think there is much hype in the steel marketing industry.

I think you hit the nail on the head there, it's a Gerber.