The Perfect Alloy

black mamba

black mamba

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Obviously, I know there is no such thing as a "perfect alloy." Knives are generally created for a specific purpose, and the design, including the choice of steel and heat treat, is created to maximize the properties one is looking for. But in looking at the properties of the CPM steels, I notice that 3V @ 59 has wear resistance of around 7 and an impact toughness of around 77, while 10V @ 63 has wear resistance of around 56 with a toughness of 16. Couldn't a middle ground be found, say a CPM-6 or 7V @ 61, with both wear resistance and toughness in the mid to upper 30s? This would be an ideal alloy for the majority of tasks, in a 4-5 inch drop point blade.

If you had to pick one alloy for an all-around 9" fixed blade to maximize both toughness and edge holding, what would you choose and why?
 
CPM 4V seems to fall into a good pocket right around what you're looking for. Has a balanced place between the two, and performs well in my experience as well.
It's equivilant is Vanadis 4E, and that steel was used by ZT in their new(ish) 0180 fixed blade that was a Hinderer colab for his Field-Tac.
 
Charr said:
CPM 4V seems to fall into a good pocket right around what you're looking for. Has a balanced place between the two, and performs well in my experience as well.
It's equivilant is Vanadis 4E, and that steel was used by ZT in their new(ish) 0180 fixed blade that was a Hinderer colab for his Field-Tac.
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Completely agree! 4V falls into the perfect alloy category better than any other I am aware of. M4 is another alloy that handles both edge retention and toughness better than most. 4V is the steel I want most right now but the selection of 4V knives is slim right now.
 
TheGearGuy said:
Completely agree! 4V falls into the perfect alloy category better than any other I am aware of. M4 is another alloy that handles both edge retention and toughness better than most. 4V is the steel I want most right now but the selection of 4V knives is slim right now.
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Ferrum Forge Ferox is the only one I know of that does it well. I'll send you an email with details.
 
black mamba said:
If you had to pick one alloy for an all-around 9" fixed blade to maximize both toughness and edge holding, what would you choose and why?
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CPM-3V @ 60Rc. Precisely why you asked - very good wear-resistance with very high toughness (around 70ft/lbs in Charpy tests). It's so durable it's almost boring to test it. There are a number of alloys that have come out over the last few years to compete with 3V in those categories, and some are really very good (probably its equal, considering the fairly small differences between them). But none that I know of really exceed it in performance for a general purpose knife blade, in any meaningful way.

Especially when you factor in availability and cost, 3V is still king of the tool steels suitable for GP/"hard use" knives. If you're willing to more than halve the toughness to get higher wear-resistance, there are lots of options. But then you're really not comparing the same class of performance at all. You drift into apples-and-oranges territory and run the risk of not using those alloys to their full hardness potential, trying to eke out toughness that just isn't there.

If a person requires better corrosion-resistance with better wear-resistance and nearly as much toughness as 3V in the 58-60Rc range, Elmax and CTS-XHP fit the bill quite well. M390 and a few other "stainless" steels have great reputations as well, but I haven't worked with them, so I can't really comment.
 
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james terrio said:
CPM-3V @ 60Rc. Precisely why you asked - very good wear-resistance with very high toughness (around 70ft/lbs in Charpy tests). It's so durable it's almost boring to test it. There are a number of alloys that have come out over the last few years to compete with 3V in those categories, and some are really very good (probably its equal, considering the fairly small differences between them). But none that I know of really exceed it in performance for a general purpose knife blade, in any meaningful way.

Especially when you factor in availability and cost, 3V is still king of the tool steels suitable for GP/"hard use" knives. If you're willing to more than halve the toughness to get say 20% higher wear-resistance, there are lots of options. But then you're really not comparing the same class of performance at all.

If a person requires better corrosion-resistance with similar wear-resistance and nearly as much toughness as 3V in the 58-60Rc range, Elmax and CTS-XHP fit the bill quite well. M390 and a few other "stainless" steels have great reputations as well, but I haven't worked with them, so I can't really comment.
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Great info man!

I can only offer that M390 is like a balance of good qualities for high-carbide stainless steels, without perticularly excelling too much in one category or another. Has lower toughness than Elmax (not by a ton), but gains wear-resistance over it, and will hold an edge better but its finer grain structure makes it easier to sharpen than Elmax to my hands.
It is also one of the few stainless steels that can operate well in both a toothy and polished edge. Either way, the cutting performace is much different than most other steels. It is the most aggressive steel I've personally ever handled (though my library of info is still lacking in many categories, I'll admit), and performs very well.

Elmax would be a good option for this debate as well. Thanks for mentioning it, because it completely slipped my mind when I thought about this.
 
here is the write up for some steel i bought
the steel is 100MnCrW5 specially modified with 0.2% vanadium manufactured by a multi-generational family business in the cliff side town of Thiers, France. located above the Durolle River, the village of Thiers has a tradition of making cutlery dating back to the 14th century. At its best when tempered to Rc62-64.
scott
 
The best practical middle ground I've had decent experience with would be M-4 and S35VN. Past that I feel the "sharpness" isn't worth the "brittleness". If that makes any sense. Good stuff bringing up M390, very similar to 3V.
 
Of course it all depends what a person means by "general purpose", too. To me that means everything from cleaning fish/game to food prep to cutting green wood for a quick shelter and processing wood for a campfire... so high toughness is important to me. And if need be, I'll sacrifice a little wear-resistance to get it.

If the most challenging thing a person ever cuts is newsprint and rope, then toughness really isn't that big of a factor. Just go for fine grain, high carbide volume, high hardness and thin geometry.
 
james terrio said:
Of course it all depends what a person means by "general purpose", too. To me that means everything from cleaning fish/game to food prep to cutting green wood for a quick shelter and processing wood for a campfire... so high toughness is important to me. And if need be, I'll sacrifice a little wear-resistance to get it.

If the most challenging thing a person ever cuts is newsprint and rope, then toughness really isn't that big of a factor. Just go for fine grain, high carbide volume, high hardness and thin geometry.
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totally, in someone like my case I moved onto 5160 and 52100 for other options, but that was for culinary where we don't have so much impact. Similarly, that's what drew me to try out what a lot of production type knives using M390 and 3V were up to for hard use. Bought a couple pieces from NJ steel to work with, but haven't had any time to research enough before messing with it comfortably. Although I know you've got a lot of experience with 3V, curious to hear your take on it for thinner harder tolerance in culinary.
 
B34NS said:
Although I know you've got a lot of experience with 3V, curious to hear your take on it for thinner harder tolerance in culinary.
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Pretty much what you'd expect... running it at 60 or 62Rc makes the most of the wear-resistance, and the toughness helps it support a very thin edge. :) Alpha Knife Supply sometimes has 1" wide pieces of 3V in .048" thickness; it makes wicked little slicers - great for real flexible filet/boning knives with a fine, durable edge. :thumbup:

Butch Harner has made a number of kitchen knives with 3V, as I recall.
 
Thanks for the great info, everyone, the 4V and M4 both look very good. 4V @ 62 has almost twice the wear resistance of 3V @ 62, and only about 10% less toughness. That is why I thought that something between 4V and 10V (i.e. 7V) alloy would give more wear resistance than 4V with more toughness than 10V. Just wishful thinking, I guess.
 
I am going to agree with you, but remove the 'probably'......!
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Says the guy with 3V's composition as his sig. :)

To be honest I like the whole class of steel beginning with 3V's uncle, Vascowear, as well as the replacements Cruwear, CPM Cruwear, PD#1, Zapp Z wear, etc., etc.

I prefer Cruwear at around rc 62 with a fairly high heat & temper for folders up to skinning type fixed blades. 3V at rc 58 for choppers. I have a CPM Cruwear Phil Wilson at around rc 63 and man can it take thin edges and slice all day!

I have 2 4V blades. One at rc 63, and one at rc 59ish and I like what I see so far but wouldn't sell my Cruwear or 3V for a 4V knife. In real life the added wear resistance is not important to me as I rarely push it that much.


joe
 
james terrio said:
Pretty much what you'd expect... running it at 60 or 62Rc makes the most of the wear-resistance, and the toughness helps it support a very thin edge. :) Alpha Knife Supply sometimes has 1" wide pieces of 3V in .048" thickness; it makes wicked little slicers - great for real flexible filet/boning knives with a fine, durable edge. :thumbup:

Butch Harner has made a number of kitchen knives with 3V, as I recall.
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That's what I figured, thanks for the heads up on Alpha as well!

I'm a huge fan of our ABS Mastersmiths here in the states, I'll have to check out his work.
 
therealmrjones said:
Can't believe nobody's mentioned INFI yet :D
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Honestly I stayed away from it because you generally can only get it in one type or heat treatment and you have to shellout quite the penny for it even new, plus a few months' wait. It's definitely an option, but not something I would put at the top of the list because of availability. Plus, it has kind of weird characteristics being a Nitrogen steel, and I have relatively little experience with them.

Trying to get my hands on Vannax and Z-FiNit to give them both a shot, but you very rarely actually see them used for knives still and they are not cheap...at all.
 
lzeplin said:
How does Elmax rate?
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I kind of find different things on Elmax depending on the heat treatment and how well it has been done in thickness and grind, but it is a very tough stainless steel that holds an edge well, and has overall good wear resistance. It is used in knives when you need a stainless specialized in toughness at higher hardnesses in my experience, and at high hardness not much can beat it for toughness in stainless, though 3V will out-perform it in that repsect at almost any hardness from what I've seen.

It has gotten a bad rep because of some production companies that ground the edges much too hot without quenching and ate through the Heat treat, but when done well it really is an excellent steel, though a little bit annoying to sharpen and not so good at taking a polished edge compared to M390, S110V, and, from all acounts, most if not all of the nitrogen steels. Still MUCH easier to sharpen than S90V.
 
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