So many knife steels

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nettlle

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Looking for a good knife steel. Been a while since I have purchased a knife. This is a knife that can be sharpened to a razor edge and hold it for a while. Every day use on a farm. Best I have now is D2 and probably would be hard to sway me away from D2. I have diamond stones to sharpen these steels.

Maybe things have changed but not of fan of stainless. Could never get stainless to retain an edge. Really these days all I look for is a good carbon steel. I can deal with the rust if necessary.
 
It doesn't really make sense to talk about "stainless steel" as if it's one thing, any more than it does to talk about "carbon steel" as if it is one thing.

There are, as you say, so many knife steels, both that qualify as high carbon steels and as stainless steels that trying to group them into a couple of categories and then trying to make blanket statements about properties like edge holding isn't really productive.

D2 is pretty close to being a stainless steel. It doesn't have quite enough chrome to qualify, but it's not far off.

If you like D2, you might look into CTS-XHP. It's supposed to perform similarly to D2 but with better edge-holding and corrosion resistance properties.

Also hard to go wrong with either S30V or S35VN. With one exception, both should equal or outperform D2 in all categories. The exception is that S30V might give up just a little to D2 in toughness.

A few others that should equal or surpass D2 in every category are: ELMAX, CPM-3V and CPM-4V.
 
I guess I should add that the list I provided above isn't anywhere near complete. For example, if you don't mind giving up corrosion resistance compared to D2, CPM-M4 is really hard to beat for toughness and edge-holding. CPM-20CV can almost equal CPM-M4, but with better corrosion resistance, not quite the same toughness, and with increased sharpening difficulty.

Here are some other resources you may find handy. Keep in mind that you will want to look at more than one as you will see opinion (perhaps unintentionally) disguised as fact in some of them. Looking at multiple sources will provide a better overall picture of the situation.

https://www.bladehq.com/cat--Best-Knife-Steel-Guide--3368

http://zknives.com/knives/steels/index.shtml

https://www.spyderco.com/edge-u-cation/steel-chart/
 
In my mind stainless steel knives were invented for those not willing to care for the blade steel well enough to prevent them from corroding. Not a bad idea. Stainless was created as a superior knife steel?
 
How to Pick the Best Steel for Every Knife is a good place to start. The author, Larrin Thomas, has a PhD in Metallurgical and Materials engineering. His father is the fairly well known Damascus steel maker, Devin Thomas.
In my mind stainless steel knives were invented for those not willing to care for the blade steel well enough to prevent them from corroding.
That's an interesting opinion, but maybe not all that accurate. Some people work on or near the ocean and need high levels of corrosion resistance. Some people have more corrosive sweat than others, and can literally make a simple carbon steel blade rust from carrying it in their pocket for one day in the summer. Some people just like having a tool that requires less maintenance. That's a different mind set, but it isn't necessarily bad or wrong.
 
In my mind stainless steel knives were invented for those not willing to care for the blade steel well enough to prevent them from corroding. Not a bad idea. Stainless was created as a superior knife steel?
Ok, this is me rambling. I don't think any of what I'm going to say is absolutely without basis in fact, but I'm also not going to try to support it with hard science either. In fact, I would welcome input/criticism from anyone who has a solid background in metallurgy.

With that caveat in place, here we go.

First of all, stainless was not created as a superior knife steel because it wasn't developed for knives at all. I believe the man credited with inventing stainless steel was actually looking for a way to make superior gun barrels. It was created as a steel that didn't rust and someone later realized that knives could be made from it.

So it wasn't invented with knives in mind, but that doesn't mean much in terms of how good it is for that application. Is stainless a superior knife steel even if that's not why it was invented?

I don't like that question because I think it's impossible to answer. There are just too many stainless steels out there to make any kind of an assessment about their superiority or inferiority to carbon steel when it comes to knives. In fact, there are a lot of carbon steels out there too, so we're comparing a wide variety of things to a second wide variety of things. Some stainless steels are superior to some carbon steels. Some carbon steels are superior to some stainless steels. Some stainless steels make really poor knife blades, some make really good knife blades.

When a question is too hard, I like to take the politician's approach. I'm not going to answer the question that was asked, I'm going to make up my own question and answer it instead. Now don't get mad just yet--I'm going to try to make up a question that has an answer that is still sort of useful, and not totally off topic.

Here's the question. Let's say we pick a carbon steel and a stainless steel that have roughly similar material properties. Similar edge-holding, similar toughness, similar hardness. That's not a crazy assumption. Maybe one time it would have been, but these days it isn't hard to find a couple of really good knife steel alloys, one stainless and one carbon that match up very well in terms of hardness, toughness and edge-holding.

So now what's the difference between them?

Well, the stainless steel will probably be a little harder to sharpen. Stainless steels tend to be a little "stickier", in my experience and that makes them a little harder to sharpen. There are other reasons some stainless steels might be hard to sharpen that may be more pertinent, but let's leave it at that. Anyway, the stainless steel might also be a little less likely to chip, but that's just me speculating (then again, so is most of this post).

The stainless steel will definitely be more corrosion resistant.

Nothing like rambling in the middle of rambling--so here we go off on another tangent. What makes a knife dull? The way I think about it, four things make a knife edge dull.

1. Wear. The edge wears away from use.
2. Chipping. Pieces of the edge break off.
3. Rolling. The edge actually bends, or rolls over.
4. Corrosion. The edge corrodes away.

Depending on how the knife is used/carried/stored, and depending on what it's made of and how it's heat treated, the mix of how much each of those affects the knife's sharpness will vary.

Why did I bring that up? Well, by choosing a stainless knife, we can dramatically reduce one of the causes of dullness--corrosion. Now, if we pick a stainless steel that has other material properties that we like (toughness, edge retention, hardness) we can get everything we would have wanted out of a carbon steel knife with the extra benefit that we don't have to worry about corrosion either defacing our knife or dulling the edge. Maybe we pay a little bit of penalty in terms of sharpening ease, but for folks willing to sharpen on diamond hones, that's a pretty minor impact.

So are stainless steels superior to carbon steels for knives? I would say that there are SOME stainless steels available these days that can outperform traditional carbon steels used in knives in most categories without giving up anything appreciable in other areas. Obviously not all stainless steels fit that description, but there are some that do.

There is one big downside. If you want a knife made out of a stainless steel like that, you're almost certainly going to pay a lot more than you would for similar performance in a good carbon steel knife.

Anyway, ignoring the fact that I might have come up with a question that simplifies the the problem down to the point that it's meaningless, now we have an answer. Yeah, a really good stainless makes a superior knife steel.

So which stainless steel should you pick? You can always just pick a maker you trust instead and look at what they are using in their premium lines. They have experts who make knife steel decisions for a living. It's a complicated subject and most of us are never going to be able to get a really good handle on it.

Or you can find a bunch of resources and see what stainless steels are commonly recommended by people who claim to know what they're talking about. If you look at enough of them and sort of "average" out the recommendations, you'll probably end up with something decent.

Or, you can do what I did. You can read a bunch of stuff, watch a bunch of videos on knife steels and metallurgy, and knife material properties, ask dumb questions in online forums, read dumb questions other people have posted in online forums and then after you've done that for a good long time, you can start pretending like you have actually learned enough useful information to be able to discourse intelligently on the topic.

It's not an efficient approach to the problem, and if you try to prove how much you've learned in public, there's a good chance you'll get slapped down by someone who's actually a real expert. So I wouldn't take that approach that unless you really enjoy studying the topic. That way even if you never really gain much useful knowledge, at least you had fun just like I did.
 
I've spent a lot of time reading about knife steels in the past few weeks. It's still all PFM for me, but I am absolutely AMAZED at the variety of steels one has from which to choose. As a young man, I thought I knew something about knives. I was wrong.
 
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Stainless was created as a superior knife steel?

Maybe things have changed


frogfur,

No

Yep

As JohnKSa has pointed out "stainless" isn't a very useful term in knives the way it used to back when all that was available in "stainless" was 440C and Vascoware. Mater of fact, "stainless" isn't even a good term any longer. High alloy steels are now available to give specific properties for knives with corrosion resistance only being one of the properties. I'm a big fan of S30V these days, but I've seen crazy things done with XHP that an edge shouldn't withstand.

So, when you say you're going to use it around the farm what are those uses? Your uses around your place can be very different than mine around my place so with so many steels available (and non steels) for blades we can help you better if we know the range of uses. Would you be cleaning hooves and cutting hay bail twine? Stripping wire, cutting zip ties, notching grafts. Castrating and lancing? Is "the farm" on the coast with lots of salt spray, in the inland alkali areas, or just riding around in a sweat soaked pocket all day? All without cleaning the blade until, maybe, the end of the day? So many different uses influence what steel to recommend.

I'm in humid Tennessee on a lake so we're kinda warm and damp or chilly and damp...did I mention damp. If I go to the coast, when I dive I want something I can rinse off and not worry about. See how my needs might be different than your's?
 
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Frogfur... all of the various steels were created to fill one or the other need.. If you worked in and around saltwater... you wouldn't have much use for steels that weren't "stainless" -and even the so-called stainless steels vary so widely in actual corrosion resistance that I'm always finding that this or that blade does not belong on my skiff since you can't keep it in good condition around saltwater.... My work blades for fish cutting (big Forschner butcher knives) aren't even kept on my skiff since they wouldn't do well there. I keep them in my truck and only use then at the end of each day on the water when they're needed (and in these days most of my customers are doing "catch and release" since they're staying in a motel somewhere...).
 
WOW! What an excellent thread with outstanding links to resources. I am D2 proponent and also like S30V and S35VN, but admittedly use my knives mostly in an office/laboratory/lunch room environment, and don't work them hard on a farm. :cool:

[edit] i forgot to mention that I like to leave my blade edges "toothy", thus I lean towards D2. Also, I find the Knife Steels Composition app from http://zknives.com useful.
 
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D2 or A2 are almost too hard for me to sharpen. I have some with those steels, like them OK for certain uses, but they are almost too much of a good thing FOR ME. Others more skilled at sharpening may love them. S30V is probably the best overall balance for me. But there are a LOT of good steels out there depending on your budget. 440C is one of the least expensive, and I'd not be afraid to own a knife made with it. Buck's version of 420HC does pretty well if you stay on top of it. It does need to be sharpened more often, but is very forgiving and easy to work with. I like the GV10 used on many Spyderco knives too.
 
JohnKSa said:
D2 is pretty close to being a stainless steel. It doesn't have quite enough chrome to qualify, but it's not far off.
Just to illustrate how easy it is to get confused on this topic, if you try to find out how much chrome it takes to make a steel a stainless steel, you won't find a hard limit.

What I stated in the quote above is generally accepted to be an accurate statement, but it's pretty misleading. If you look solely at the alloy composition, D2 DOES have enough chrome to be stainless. As little as 10.5% chrome could be enough to qualify a steel alloy as stainless and D2 can actually have as much as 13%.

Here are two more cans of worms, by the way. (Yeah, I'm rambling within another rambling again. Deal with it.)

1. If you look at different sources, you'll find that D2 isn't one specific, tightly controlled combination of elements. Some sources list D2's chrome content as 12% while some say it can be anywhere in the range of 11% to 13%. So even when we talk about specific alloys, those names may actually encompass a group of steels with compositions that fall into a certain range as opposed to a one careful recipe.

2. Maybe you're the kind of person who doesn't simply read something posted by an anonymous person on an online forum and take it at face value. (Good on you!, by the way--but stop that when you're reading my stuff.) So you looked up the amount of chrome in stainless steel and what I posted above doesn't look right to you. Well, there are actually several "families" of stainless steels. Austenitic stainless steels generally need a minimum of about 16% chrome, while martensitic stainless steels only need about 11.5% and ferritic stainless steels (not used in knives as far as I know) only need about 10.5%. Duplex stainless steels start at about 19% chrome. All that sounds cool, right? I'm sure it is, but don't ask me to explain all the differences in all the various stainless steel "families". I don't even know all their names, let alone what they mean. But don't get the idea that the only difference between them all is how much chrome they have in them--that's just one difference.

Anyway, so D2 has a lot of chrome in it, but people still say it's not really a stainless steel--why is that? Well, it's because some of that chrome is used up forming carbides with the carbon content of the steel. The amount of chrome that is used up forming carbides isn't available to make the resulting alloy corrosion resistant. In other words, even when we can nail down a specific ingredient in a steel alloy to an exact amount, just knowing how much is in there doesn't always tell the whole story.

A little thought will reveal that some of the carbon is also being used up to form the carbides, and a little more will suggest that means that carbon , like chrome, can also do least two different things in a steel alloy. So when a carbide forming metal is added to a steel recipe, some of the carbon in the alloy is stolen to form carbides--which means you need to add more carbon to do the stuff that it was doing in the previous alloy. You know, distorting crystal lattice structures to add strength and all that... So again, just as with the chrome, only looking at the amount of carbon in the alloy doesn't tell you the whole story.
 
Frogfur... all of the various steels were created to fill one or the other need.. If you worked in and around saltwater... you wouldn't have much use for steels that weren't "stainless" -and even the so-called stainless steels vary so widely in actual corrosion resistance that I'm always finding that this or that blade does not belong on my skiff since you can't keep it in good condition around saltwater.... My work blades for fish cutting (big Forschner butcher knives) aren't even kept on my skiff since they wouldn't do well there. I keep them in my truck and only use then at the end of each day on the water when they're needed (and in these days most of my customers are doing "catch and release" since they're staying in a motel somewhere...).

This was Dad's boat:

pEFB2ub.jpg

Until you live on or next to salt water you have no idea how quickly things corrode. Everything electrical shorts out in time.

You know, I have a number of Case CV knives, no idea what the steel is, but they are great, take a good edge. A shooting bud of mine, his Dad gave him this Case Canoe in 1964, and the weekend prior to this picture he had field dressed a deer, and had not cleaned the knife! Yuke!

vhYnLb5.jpg

But, the knife is still cutting after all those decades.

I have no idea what Mora uses but this carbon steel knife is sharp, and cheap! Can't beat that combo


zzgya1C.jpg

This Boker Johnny Reb Bicentennial was made in 1095.

Y8qMzD7.jpg

I have a number of 1095 knives, they all take an excellent edge, easy to sharpen, its a good steel.

9oiPHkv.jpg

Moore Maker made this one in 1095 and is still making them:

Mdw2ZUa.jpg

Kabar makes a 1095 cro van, and the Kabars I have with that steel are wicked sharp.

I prefer something stainless because I hate and fear rust. I wish I could say I had a favorite stainless, I really like D2, and Carpenter CTS-XHP, and a bunch of other stainless knives. Still have some Buck knives in 420HC. The heat treat is more important than the steel, in my opinion.
 
Looking for a good knife steel. Been a while since I have purchased a knife. This is a knife that can be sharpened to a razor edge and hold it for a while. Every day use on a farm.
Mora makes a good "farm knife". Low cost. Good blade. I bought 5 and have them in different locations on our farm. Two barns have Mora's on stand by. One in one garage, one in the other. One in the machine shed. Great little farm knife.
 
The heat treat is more important than the steel, in my opinion.
It's certainly possible to ruin a really good alloy with a bad heat treat. Also to tailor a fairly run of the mill alloy to be really ideal for a particular task with a good heat treat. The capability has to be in the alloy before you can bring it out with the proper treatment, but yes, how that treatment is done is very important.

By the way, heat treatment can be really complicated with stainless steels--or really simple--austenitic stainless steels aren't really heat treated for hardness at all.
 
First of all, stainless was not created as a superior knife steel because it wasn't developed for knives at all. I believe the man credited with inventing stainless steel was actually looking for a way to make superior gun barrels. It was created as a steel that didn't rust and someone later realized that knives could be made from it.
Yes and no. According to Cobb, as cited by Thomas:
The person credited with starting the industrial use of stainless steel was Harry Brearley. Yes, Brearley's research was focused on a steel for gun barrels. No, it wasn't someone else who realized that the corrosion resistant steel would be good for knives. It was Brearley himself who figured it out, but it did take him a couple of years to get someone to start making knives from it. Brearley's patent for this first mass produced stainless steel was listed as "Cutlery". Hence, Thomas contends that the first stainless steel actually was for knives - https://knifesteelnerds.com/2018/07/16/first-stainless-steel-for-knives/

Just to illustrate how easy it is to get confused on this topic, if you try to find out how much chrome it takes to make a steel a stainless steel, you won't find a hard limit.

What I stated in the quote above is generally accepted to be an accurate statement, but it's pretty misleading. If you look solely at the alloy composition, D2 DOES have enough chrome to be stainless. As little as 10.5% chrome could be enough to qualify a steel alloy as stainless and D2 can actually have as much as 13%.
You may find this article interesting - https://knifesteelnerds.com/2018/06/11/how-much-more-chromium-does-d2-need-to-be-stainless/

By the way, heat treatment can be really complicated with stainless steels--or really simple--austenitic stainless steels aren't really heat treated for hardness at all.
Likewise there are low alloy, simple, carbon steels that generally have simple heat treats; and there are high alloy, complex, carbon steels which generally have more complex heat treats. From what I understand, which may be completely wrong, it's the complexity of the alloy, whether stainless or not, which generally correlates to the complexity of the heat treat.
 
Hence, Thomas contends that the first stainless steel actually was for knives ...
Interesting. I knew Brearly developed stainless steel in the quest to make better gun barrels; I didn't realize that the first commercial use appears to have been for cutlery.
...there are high alloy, complex, carbon steels which generally have more complex heat treats.
I didn't know that. That's the fun part of this topic--there's just so much to learn. For example, earlier I was reading about carbides and found out that you can get various types of carbides even with the same ingredients.
 
Some really good advice and some really good links that is much appreciated. Need to read up on these new corrosion resistant steels. Have not keeping myself up to date and formed an opinion many years ago that seems to be no longer true now.
 
It's certainly possible to ruin a really good alloy with a bad heat treat. Also to tailor a fairly run of the mill alloy to be really ideal for a particular task with a good heat treat. The capability has to be in the alloy before you can bring it out with the proper treatment, but yes, how that treatment is done is very important.

By the way, heat treatment can be really complicated with stainless steels--or really simple--austenitic stainless steels aren't really heat treated for hardness at all.

Without standardized tests, it is impossible to objectively compare knife steels. To date, discussions about compositions and what this element does, or does not do, read more like a witches potion "Eye of newt, toe of frog". There are real differences between knife steels, but how much of a difference is all anecdotal. Some have tried to address this in various ways, and I wish the community would come up with agreed on standards for angles, edges, and cutting media. Then we could compare and see if toe of frog really improves the steel or is just a distinction without a difference.

And knife steels are so "soup du jour", what was an advanced steel five years ago is so 1999. I thought AUS 8 was a great steel, but hardly anyone would agree now. Based on my skepticism, all I can say is that knife steels are the best they have ever been, we live in great times and lots of wonderful choices. The steel in older knives was either "Solingen steel" or "surgical steel", Randall blades described as 440 steel were 440 A, which is disappointing as at the time they wanted us to think it was 440C. At least today we are finally finding out what is being used. And based on my experiences with older knives and today's edges. I can tell some steels seem to hold their edges longer, but I don't know if that is due to edge geometry or not, and some steels are much harder to sharpen, regardless of edge geometry.

At least 1095 steel then is as good as it is today. My Bokers from the 1970s' take a good edge and hold them as long as modern 1095.

Case still makes a Sodbuster in carbon steel, this one is stainless, but I have lost a number of carbon Sodbusters in the past. It is a good, simple knife for the price.

TIUnP04.jpg
 
There are standardized tests, but things get complicated.

It's not like you can say that with test A you get such and such result with alloy X and so a knife made from X is better than a knife made from Y. Because, as you say, the heat treatment makes a difference. And the tempering makes a difference. And the knife community doesn't play with raw alloys, they play with knives. And the knife design makes a big difference in how it performs.

So you have a set of graphs from standardized tests showing all the material properties for alloy X based on heat treatment variables. Then you'd need another complete set based on tempering variables. Then you'd have two similar sets of graphs for alloy Y and you would compare all the graphs and see that at a given austenitizing temperature and a given tempering temperature that alloy X is the same as alloy Y in terms of hardness but maybe Y is better in terms of toughness, and edge holding.

Yay!--Y is better than X. All done...except that no one cares about two chunks of metal, they want knives.

So a knife maker takes alloy Y, heat treats it differently from the recommended temperature, tempers it differently from the recommended tempering temperature--because what do the metal companies know, they aren't knifemakers, dontcha know! Maybe he also puts a poor edge geometry on it, and then sells it as a knife that's obviously better than some other knife made of alloy X because everybody knows that Y is better than X (Yay!).

But the knife community can tell that the knife made from X actually works better than the knife made from Y--and nobody knows how the knife maker heat treated or tempered the knife, and maybe many people don't realize that the edge geometry of the knife is a big part of why the knife made from alloy Y doesn't perform well.

So now alloy Y gets a bad reputation and X gets a good reputation, and the one or two guys who are genuine experts and actually understand metallurgy try to explain what's going on and are vilified and get banned from forums because they are clearly saying stuff that doesn't align with what's happening in the real world...

But we started out with standardized tests--how could all this happen?

Which is why maybe it's better to just "pick a maker you trust instead and look at what they are using in their premium lines. They have experts who make knife steel decisions for a living. It's a complicated subject and most of us are never going to be able to get a really good handle on it."
 
Since I'm a saltwater guy (understatement) all I can do is actually use one blade or other (all marked stainless...) and find out what actually works...These days the relatively inexpensive blades kept on my skiff (mostly for bait chunking or bait rigging - but also for fileting thin skinned fish like spanish mackeral and speckled trout...) are actually from Chicago Cutlery - their commercial working knives for want of a better descriptor... Their plain wood handles offer a great grip when my hands are bloody, greasy, and just not what you want your mitts to be when working with knives - and they've held up better as far as corrosion resistance than other much more expensive blades...

and for anyone wondering what my world looks like - here's a report from this weekend on another site...
https://www.microskiff.com/threads/fishing-report-14-june-flamingo-gulf-coast.66734/#post-599618
 
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