Corrosion resistance of CPM 3V

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leeramundo

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I'm looking into getting a Bark River Gunny in 3V but am a little concerned about it not being as corrosion resistant as I'd like. The other options for this knife as far as I know are A2, S35VN, and Elmax. 3V is more corrosion resistant than A2 as far as I know, obviously Elmax and S35VN are stainless, but as I understand it, 3V has better edge holding capabilities than S35VN, and I think Elmax is kind of overkill for me and my wallet. So 3V seems to be top choice right now. However I live on the West Coast, and with the salty sea air here, I'd really like a steel that isn't horribly susceptible to rust. How does 3V compare to 1095 and CPM M4 as far as rust resistance goes, because these are a couple of steels I'm pretty familiar with. I'd like it to be at least noticeably more resistant than both of these for an outdoor knife like this.

Thanks
 
According to Crucible, 3V has about the same abrasion resistance as CPM 154, which is lower than S30V or S35VN. It is going to be more corrosion resistant that 1095, but that I had heard is that when it does corrode, it pits as opposed to just getting surface rust. Elmax is good stuff, but I think that lot of folks are thinking now that you might be wasting your money unless it is hardened to 60Rc+. It is said that it is a completely different animal at those higher hardness levels. A lot of folks on here can fill you in on S35VN. As for M4, very few steels will be more abrasion resistant than that stuff if it is properly heat treated.
leeramundo said:
I'm looking into getting a Bark River Gunny in 3V but am a little concerned about it not being as corrosion resistant as I'd like. The other options for this knife as far as I know are A2, S35VN, and Elmax. 3V is more corrosion resistant than A2 as far as I know, obviously Elmax and S35VN are stainless, but as I understand it, 3V has better edge holding capabilities than S35VN, and I think Elmax is kind of overkill for me and my wallet. So 3V seems to be top choice right now. However I live on the West Coast, and with the salty sea air here, I'd really like a steel that isn't horribly susceptible to rust. How does 3V compare to 1095 and CPM M4 as far as rust resistance goes, because these are a couple of steels I'm pretty familiar with. I'd like it to be at least noticeably more resistant than both of these for an outdoor knife like this.

Thanks
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From personal experience, corrosion resistance least to most- M4, 1095, 3V. 3v is termed a "semi" stainless, and in my use and storage of it, will not exhibit much corrosion, in my use in East Coast woods and some brackish water (Chesapeake Bay) use. I got soaked on a hike with my M4 Gayle Bradley in my pocket, and forgot to dry it, next day it had rust on it. Fastest I have seen on a steel. Cleaned and forced a patina, fine now. As long as you maintain properly none of those steels will treat you wrong I think, but 3V is what I would pick.
 
Danketch said:
From personal experience, corrosion resistance least to most- M4, 1095, 3V. 3v is termed a "semi" stainless, and in my use and storage of it, will not exhibit much corrosion, in my use in East Coast woods and some brackish water (Chesapeake Bay) use. I got soaked on a hike with my M4 Gayle Bradley in my pocket, and forgot to dry it, next day it had rust on it. Fastest I have seen on a steel. Cleaned and forced a patina, fine now. As long as you maintain properly none of those steels will treat you wrong I think, but 3V is what I would pick.
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Just to clarify, this was with M4, not 3V steel right?
 
Like all steels, the corrosion resistance of 3V is greatly effected by the heat treat which determines how much free chrome there is. Since it's such a borderline material in it's corrosion resistance, this detail can have a very noticeable effect, so one can't make a broad statement. I have seen 3V be almost as stainless as 440C.
 
Nathan the Machinist said:
Like all steels, the corrosion resistance of 3V is greatly effected by the heat treat which determines how much free chrome there is. Since it's such a borderline material in it's corrosion resistance, this detail can have a very noticeable effect, so one can't make a broad statement. I have seen 3V be almost as stainless as 440C.
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How does this affect toughness? more corrosion resistance vs toughness.
 
Cobalt said:
How does this affect toughness? more corrosion resistance vs toughness.
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I'm not sure I can draw a line between the two as it applies to 3V. Tweaks that are applied to 3V to improve its durability in some applications can result in more free chrome as an unintended side effect, but it's not due to the additional free chrome. It has more to do with keeping the carbon in the martensite and out of the carbides. The improvement to corrosion resistance is a happy accident.

In a steel like 3V with a moderate amount of chrome I don't know if it is as detrimental to toughness as it is in a high chrome stainless. Perhaps if some were removed the steel would be tougher, but maybe not, I don't know.
 
Nathan the Machinist said:
I'm not sure I can draw a line between the two as it applies to 3V. Tweaks that are applied to 3V to improve its durability in some applications can result in more free chrome as an unintended side effect, but it's not due to the additional free chrome. It has more to do with keeping the carbon in the martensite and out of the carbides. The improvement to corrosion resistance is a happy accident.

In a steel like 3V with a moderate amount of chrome I don't know if it is as detrimental to toughness as it is in a high chrome stainless. Perhaps if some were removed the steel would be tougher, but maybe not, I don't know.
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Possibly but 5% chrome in A2 and std A8 didn't help toughness and mA8 is actually tougher.
 
[video=youtube;bNo2YUe-mbQ]https://www.youtube.com/watch?v=bNo2YUe-mbQ[/video]
 
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