High Carbon vs Stainless Steel for general use

[Bobby B]

In another thread, our fearless moderator, the great Obi-Ron, stated that high carbon steel was better than stainless in all categories except corrosion resistance.
1) Ron: Does this mean that the Bowie (SK5) is a better all around choice than the Trident (440C)? They are essentially the same knife (price,size, etc.).
For general use, i.e. non-SEAL or diving, would you recommend the Bowie over the Trident?
2) Everyone: preferences on carbon vs stainless, and why?
Thanks,
Rob

 

[Crayola]

SK5 probably would be better for the knfie you describe than 440-C. Indeed, most stainless steels beat carbon steels only in corrosion resistance. 420V outperforms some carbon steels in edge holding, though I think it takes a hit in toughness.

As a general rule, a good carbon steel will outperform stainless steel, except in stain resistance. If you will oil your knife and otherwise care for it, a carbon steel will be stronger and take a better edge than a simple stainless steel. If you won't care for your knife, a good stainless is your best bet.

 

[Cliff Stamp]

Crayola :

a carbon steel will be stronger and take a better edge

The high carbon, high alloy stainless steels commonly used today like ATS-34 are far stronger than simple carbon steels. They also have a much greater wear resistance. However they will also have a far lower impact toughness and ductility and will tend to pit when they corrode.

In regards to edge quality, a fine grained low alloy carbon steel like 52100 will take a higher polished edge than ATS-34. However the level of skill necessary to achive this is very high and it is a level of sharpness far beyond the ability to push shave without skin irritation.

Note as well, that for the same reason that the ultimate polished edge is not obtainable for the larger grained, large carbide stainless steels, they will tend to out slice the carbon steels at identical geometries.

-Cliff

 

[Ron Andersen]

Hi Rob,

Sorry for not answering your question in a more timely fashion. This is not my usual response time. I'd meant to return to your question when I had a few moments, but forgot...Sorry!

I'll answer your question more on a layman's level (I find this is more user-friendly for all readers to understand).

440C (actually, we use the similar Japanese steel of AUS8A) is one of the more desirable of the Stainless steels. It has of late been overshadowed by some of the newer "super steels" (like ATS-34 or BG-42, among a handful of others). It will serve most all users very, very well and adds corrosion resistance (over carbon blades).

SK-5 (I'm told is very similar to 0-1) is a carbon steel and does have outstanding user qualities, outperforming the stainless steels. But from my perspective, the average user will not notice a marked difference (of course a more serious user will). Many people do not take care of their knives or use them in humid climates. In these cases, I would recommend a stainless steel. If regular maintenance or a bit of surface rust are things the user does not mind, go the carbon steel route.

In choosing either the Bowie or the Trident, my normal response is whichever is more appealing. Just go into it with the above stated reasons in mind.

If you need anything else answered, please let me know?

 

[Bobby B]

Thanks for all the input.
My question was about "general use", which includes food prep:
I did a search on Tuff cloth and food, and understood (perhaps incorrectly?) that while Sentry cannot legally recommend their product for food prep, their "unofficial position" is that as long as there isn't "excessive product" on the blade, it should be OK...
That being said, how does the "safe" mineral oil behave on the leather handle of knives such as the Bowie? I understand it is actually very good for stag handles, and moisturising skin, so I would think it might actually be good for the handle as well?
Any thoughts?
Rob

 

[Ron Andersen]

Hi Bobby,

For the leather handle, any good leather care product should be fine. I've personally used oil on the leather handle, but I've heard it can crack the leather over time. I just don't know for sure about that.

Renaissance Wax is said to be outstanding. That's what I've recently been using.

Tuf-Cloth is outstanding for carbon blades (any blades, for that matter). I'll pass on commenting whether or not it's safe to ingest and refer you to the manufacturer (Sentry Solutions).

 

[Bobby B]

Ron,
How are the leather handles made? Are they stacked and epoxied?
How are they shaped, for exmample, the finger grooves? Are they essentially "filed" in?
Is it the same for the Micarta handles on the Trident?
Rob

 

[Ron Andersen]

Originally posted by Bobby B
Ron,
How are the leather handles made? Are they stacked and epoxied?
How are they shaped, for exmample, the finger grooves? Are they essentially "filed" in?
Is it the same for the Micarta handles on the Trident?
Rob

I've never been over these issues with Spencer. They certainly are stacked and epoxied. I'm assuming they are ground/shaped/filed/sanded once on the knife. I'll check into this as well as your other million questions. (You don't tire me out!)

 

[Bobby B]

Maybe I could try spell checking my questions...
I can outlast you with questions... I just type them, you have to go find the answers...
Seriously though, I do appreciate your time; I hope SOG does too.
Thanks, I look forward to lots of in depth answers
Rob

 

[Crayola]

Cliff: Indeed, I believe everything you said is correct. However, recall that my statement was a GENERAL one. I said:

As a general rule, a good carbon steel will outperform stainless steel, except in stain resistance. If you will oil your knife and otherwise care for it, a carbon steel will be stronger and take a better edge than a simple stainless steel.

For the 2 knives that Bobby is considering, a steel similar to O1 would outperform a large bowie made of 440-C, as long as the knife was cared for.

ATS-34 is a kickass steel. Just look at the work done by Hossom and the Strider guys! You can beat ATS-34 up pretty good, as long as the grinds and heat treat are done right. But if you want the most aggressive cutting steel, CPM-10V takes the cake. If you want toughness maxed, isn't CPM-3V the stuff? And that isn't stainless either.

As a GENERAL rule, a good carbon steel can outperform many stainless steels, except in corrosion resistance. Take a knife liek Wally Hayes' Tac-1, which he makes in O1 and 154-CM. The O1 model he says is preferred by the users he designed the knife for, because the knife can take abuse more than the 154-CM. And it takes an edge as good or better than 154-CM.

Sure the CMP wonder stainless steels, or BG-42 can outperform many carbon steels, but again, my statement was only a general rule type of statement.

Cliff, please correct me if I am wrong in anything I have said. You know more about metallurgy than I for sure!!

 

[Ron Andersen]

Crayola,

Originally posted by Cliff Stamp
Crayola :
The high carbon, high alloy stainless steels commonly used today like ATS-34 are far stronger than simple carbon steels.
-Cliff

You may wish to check if any quality knives are being made of "simple carbon steels." Most respected carbon steel knives are made of high carbon tooling steels and cannot be catagorized as "simple."

 

[Crayola]

Ron: It was Cliff that made that particular statement which you quoted, though there are SEVERAL holes in my understanding of metallurgy. I think by simple Cliff means something like the 10XX series, or O1. Compare those steels to ATS-34 or a complex carbon steel like CMP3V and the difference becomes apparent.

 

[Cliff Stamp]

Crayola :

a steel similar to O1 would outperform a large bowie made of 440-C

I would agree, but not because the O1 blade would be stronger, or take a better edge. In fact most O1 blades are differentially tempered and thus it would be *far* weaker than a uniformly hardened 440C blade. However, as you noted, the significant problem with stainless steels is the durability. If you really leaned on the above two bowies, by chopping them into hard materials, pounding on the spines with hard objects, and doing hard snaps on the edge, the O1 blade would be a better choice.

As a GENERAL rule, a good carbon steel can outperform many stainless steels

If you compare simliar alloy contents with just the Cr% being different then, yes. However the problem is the above falls apart as soon as the alloy content is radically different and you can just as easily say that a good stainless steel will outperform many carbon steels even ignoring corrosion resistance. For example take two blades, one of 1095 and one of 420HC both at 58 RC. The 420HC one will be significantly stronger with greater wear resistance. D2 however will be far stronger than 420HC as well with greater wear resistance. CPM-420V however is stronger and more wear resistant than D2, etc. . The same is true of the other properties like impact toughness and ductility. 420HC for example at around 56-58 RC is far tougher with a much greater ductility than M2 at 62-64 RC.

The generalization may have been true quite some time ago when there were few steels being used in cutlery and thus there were two broad classes "stainless" vs "carbon" with very little overlap between the two. However this is not the case now and there are many cases where the properties overlap significantly and thus the generalization falls apart badly. It is not like it is "wrong", as it is rooted in fact, but just that with the current state of quality cutlery you just have to look at the steel choice in more detail as the properties go all over the place among the various steels.

Ron :

You may wish to check if any quality knives are being made of "simple carbon steels."

Mastersmith blades being an obvious example. Even steels like 52100 are simple steels as compared to the common high alloy stainless steels like ATS-34, VG-10, BG-42, not to mention steels like CPM-420V etc. .

-Cliff

 

[Ron Andersen]

I'm aware that the term "simple" in relation to steels is a vague term at best. From my perspective (and those I've referred to who are into metallurgy), a simple steel is not an alloy. Steel is basically comprised of Iron and Carbon. An alloy adds other elements.

A simple steel would be like the “10” series (Iron with 95% Carbon). 52100 adds Chromium, thus making it an alloy steel (the Chromium is there to add harder Chromium carbides for extra edge-holding characteristics). There is always a purpose for adding additional metals to a simple steel for specific purposes, such as edge-holding, toughness, corrosion resistance, etc.

Maybe some will call a low alloy steel simple, but steels like “0” series and “D” series cannot be called simple because of their complexity.

 

[Cliff Stamp]

Ron :

a simple steel is not an alloy

Steel itself is an alloy of Iron and Carbon. An alloy steel simply has other elements, ie., it is an alloy of steel and something else in a non-trace quantity. In regards to my comment about simple steels, to suit your defination simply alter it to read :

The high carbon, high alloy stainless steels commonly used today like ATS-34 are far stronger with a greater wear resistance than many commonly used carbon steels with a much lower alloy content.

Note the Mastersmith knives mentioned in the above are often made of plain carbon steels like 1084, which would be simple steels even by the standard you reference.

-Cliff

 

[Ron Andersen]

Hi Cliff,

I certainly do not want this to be a “who-is-right” debate or to disrespect you. I just need to clear the “air” up a bit.

Originally, you compared a high alloy stainless steel to a simple carbon steel.

The high carbon, high alloy stainless steels commonly used today like ATS-34 are far stronger than simple carbon steels.

My response was to clarify that our conversation here was comparing a high alloy carbon steel (like O-1) to a high alloy stainless steel (like AUS8A). Your example detracted by comparing a non-alloy (simple) carbon steel to a high alloy stainless steel.

Yes, some Mastersmiths may use 52100 or 1095, but just the fact that they use it does not make them the best of “carbon steels” (though I’m uncertain if you were attesting to them being the “best,” but you brought this category of steel into the discussion). Obviously, the addition of valuable alloys are there to enhance various aspects of the the basic (simple) steel.

According to the Machinist Handbook, “standard steels can be divided broadly into three main groups:”

• Carbon Steels – A steel qualifies as a carbon steel when its manganese content is limited to 1.65% (max), silicon to 0.60% (max), and copper to 0.60% (max). [definition continues…]
• Alloy Steels – Alloy steels comprise not only those grades that exceed the element content limits for carbon steel, but also any grade to which different elements than used for carbon steel are added, within specific ranges or specific minimums, to enhance mechanical properties, fabricating characteristics, or any other attribute of the steel….In a technical sense the term alloy steel is reserved for those steels that contain a modest amount of alloying elements (about 1-4%) and generally depend on thermal treatments to develop specific mechanical properties. [definition continues…]
• Stainless Steels – Stainless steels are high-alloy steels and have superior corrosion resistance to the carbon and conventional low-alloy steels because they contain relatively large amounts of chromium. Although other elements may also increase corrosion resistance, their usefulness in this respect is limited. Stainless steels generally contain at least 10% chromium [in knife circles, greater than 12-13% is more commonly accepted as standard], with or without other elements. [definition continues…]

A “simple” carbon steel is likely more ambiguous than even these categories, but likely restricts itself to non-alloy carbon steels.

You had stated:

Steel itself is an alloy of Iron and Carbon.

In light of the Machinist Handbook (likely the best recognized standard we have), it seems like you might be mistaken.

There are much better forums here to discuss the advanced aspects of steels. Here, we deal mostly with user-friendly definitions and moderate (but as accurate as possible) generalizations. We’ll leave the super-techie stuff for seasoned metallurgists in the appropriate forums.

 

[Cliff Stamp]

Ron :

Originally, you compared a high alloy stainless steel to a simple carbon steel.

Since you disagreed with what I was calling a simple carbon steel I simply clarifed what I meant by the term and that yes it included low alloy carbon steels as well as the pure carbon ones, so it referred to both steels like O1, 52100 as well as pure carbon steels like 1095. There was no retraction, the two statements say the same thing, the latter one just includes the defination of simple steel that I had in mind when I wrote the former.

It is a common misconception that low allow carbon steels like O1 have a greater wear resistance than common cutlery stainless steels or are stronger and this is simply false (the strength issue is really off due to the difference in the heat treats used) - when the stainless steels are high carbon very high alloy, as are commonly used in cutlery.

To clarify, there is an exception to this, since the non-stainless steels are inherently tougher they can be hardened to a much higher RC and still remain functional. It may indeed be the case that simple steels like W1 at 64-66 RC would outlast stainless ones at 59-60 RC, but I can't think of anyone who offers such blades in the cutlery industry outside of Japanese laminated chisels, which I have little experience with.

If you move beyond simple steels, you can easily get muchgreater strength and wear resistance out of non-stainless steels. For example, M2 has 9 times the alloy percentage as O1, and will give much greater edge holding ability than the above stainless steels as well as will allow a greater cutting ability by raising the functionality of low cross section edges.

Yes, some Mastersmiths may use 52100 or 1095, but just the fact that they use it does not make them the best of ?carbon steels?

That was not the point, you made the statement that no "quality" knives were made of simple steels, your presupposition is incorrect by both the defination I had in mind when I used the term, and even the one you stated - unless you want to claim that Mastersmith level blades are not quality knives.

As for steel being an alloy, no you are not going to see that in something like a Handbook, you will want to look at something more fundamental, try a materials text.

-Cliff

 

[Ron Andersen]

Hi Cliff,

Let me clear up your misconceptions. You said:

Quote by Cliff:

...you made the statement that no "quality" knives were made of simple steels...

This is not true. Let me quote myself:

Quote by Ron:

Most respected carbon steel knives are made of high carbon tooling steels and cannot be categorized as "simple.

Note I did not say “no quality knives were made of simple steels.” That conclusion would be a misinterpretation on your part.

Quote by Cliff:

...the defination [sic] I had in mind when I used the term...

Cliff, we try to use more main-stream definitions here. Also, you can ascribe a definition to a word, but unless you explain your terminology, we can only interpret them with more standard and commonly recognized guidelines. There are drawbacks to talking over people’s heads.

BTW, I do not consider O-1 a “simple steel” because of the various alloys present. To me, a simple steel is primarily only iron and carbon, like the “10” series. (Remember, Cliff, that the term “simple” is highly vague with differing opinions on its meaning.)

I would again recommend to you, Cliff, to further discuss your theories in metallurgy in one of the other forums that specialize in these topics. This level of specifics are not the goal of the SOG Forum.

 

[Cliff Stamp]

Ron :

I did not say ?no quality knives were made of simple steels.?

Your statement :

You may wish to check if any quality knives are being made of "simple carbon steels

obviously implies it, as does the context in which it was used. The purpose of your statement was very clear - it was to refute the one I made comparing stainless steels to "simple carbon" steels. Basically your argument was that quality blades were not made of "simple carbon" steels and thus the arguement I presented was moot. This is, as pointed out in the above, not the case as many blades -of the highest quality- are made of even plain carbon steels (1084 etc. ). So the above statement I made holds no matter what defination of "simple steel" you care to use.

that the term ?simple? is highly vague with differing opinions on its meaning

Which is why I clarified what I meant by it when asked. The reason I used the term is that it is commonly used to regard the steels I mentioned in the above for many reasons, Crayola for example immediately knew what I was talking about. Look at issues like, ease of work in general, can/can't be readily forged, easily annealed, strong machinability, low soak temperatures, low responce to deep cryo / multiple tempers, very stable in responce to time variation during heat treat, used over a wide variety of blades etc., etc. .For example look at how Bill Bryson refers to O1 in "Heat Treatement , Selection and Application of Tool Steels" - a "general use", "workhorse steel", etc. .

And yes such terms are not rigidly defined, and yes, there I would assume lots of people would refer to O1 as a complex steel depending on what they are used to working with. I know a maker who does a lot of work in mild steel, he would regard O1 as a very high carbon, high alloy steel. For someone who works with D2, M2 etc., a difference perspective will be formed. It is like the tool steel label. I have seen definations that will label 1095 as such and others that refer to it as a plain carbon steel, same with ATS-34 I have seen it both for and against. In any regards the issue is of no consequence as I have already defined what I meant by the term, so it is the *content* of the defination that is the relevant issue, not to mention that the original statement holds even if your defination of the term is used.

I would have of course edited the original post to reflect the term clarification if we had the discussion in email, but since it has been responded to and quoted I am obviously not going to do that.

-Cliff