LC200n corrosion resistance

[Surfingringo]

I spent the last week testing my tusk for corrosion resistance. I have taken in out in my kayak every day for a week and when I get in the knife stays inside the hull laying in a humid compartment in a half inch of saltwater. After a week there was zero corrosion on the blade. There was some very light swirls showing around the screws which wiped right off. This happens even with my salt knives though. The hardware is extremely corrosion resistant steel but even it will start to show light corrosion given enough time in an extreme environment. The blade itself though showed none...zero. What's even more important was that there was no degradation in sharpness. The apex is usually one of the first areas to be attacked by corrosion but the lc200n performed at "H1" levels in this regard.

I hope Goldenspydie chimes in as he has done some similar testing. His copy showed some light corrosion on the blade but given the way mine has performed this makes me curious. I wonder if those spots could have come from the hardware or been the result of residue of other metal left on the blade from the grinding wheel.

[bearfacedkiller]

I was just about to post a similar thread about my S110V mule. Do you use it for fish work or bait. Could oils from fish be protecting it a little? Just trying to think of all variables. I just had an experience like that processing an elk and it got me thinking. I am putting some pics together for a thread.

[Surfingringo]

I was just about to post a similar thread about my S110V mule. Do you use it for fish work or bait. Could oils from fish be protecting it a little? Just trying to think of all variables. I just had an experience like that processing an elk and it got me thinking. I am putting some pics together for a thread.

Nah, I just stashed the knife and didn't even use it all week. Just had it cooking in the saltwater inside the hull. I have tried similar experiments with s90v and it shows a lot of corrosion after 24 hours and starts rusting and pitting within a few days. LC200n is for real when it comes to corrosion resistance.

[endgame]

Someone try the to keep it in wet shorts all day thats the ultimate test its stays moist.pluss still gets oxygen wich speeds up rust compared to full submersion

[Surfingringo]

Hey Endgame, this knife was stored vertical in a small compartment with 1/4-1/2" of water in the bottom so though sitting in saltwater, most of the knife was exposed to air. The compartment gets very hot too so the water slowly evaporates leaving salty residue on everything. Corrosion shows up very quickly on anything left in there.

[GoldenSpydie]

I hope Goldenspydie chimes in as he has done some similar testing. His copy showed some light corrosion on the blade but given the way mine has performed this makes me curious. I wonder if those spots could have come from the hardware or been the result of residue of other metal left on the blade from the grinding wheel.

Yep, I'll take a look at it sometime soon and report back whether I think it is rust or residue from something else. I might also take it to Spyderco and have them take a look at it.

For now, here are the pictures I posted previously:

[Surfingringo]

I hope Goldenspydie chimes in as he has done some similar testing. His copy showed some light corrosion on the blade but given the way mine has performed this makes me curious. I wonder if those spots could have come from the hardware or been the result of residue of other metal left on the blade from the grinding wheel.

Yep, I'll take a look at it sometime soon and report back whether I think it is rust or residue from something else. I might also take it to Spyderco and have them take a look at it.

Thanks GS, I will be eager to see what you find with yours. I have a feeling that this steel might find its way into some new salt models so I definitely would like to know as much as possible about its corrosion resistance properties. I will try to to some longer period testing with mine to see if I can force it to rust but I have had no luck so far.

[PolarisDesu]

Hey guys, sorry to step in, I just wanted to know if you know of a place where I can check the corrosion resistance index of the steels like in a chart? But not only for NaCI (Salt) but for acids too. If it exists of course...

For example, here is the Datasheet of the S110V but to be honest, I find rather strange to understand that coefficient for the corrosion resistance index for NaCI, but still it is a pretty small sample. And I found this Datasheet for the LC200n steel, but I guess it is worst... And have no idea where to find the Datasheet for the H1 steel.

For some reason I am getting attracted to high corrosion resistance, I am new to knives, but I am sure that my next knife is going to be one like H1 or LC200n.

I will be looking forward for your response!

[mattman]

Corrosion resistance for a given alloy can vary greatly depending on its post-processing/heat-treat, so trying to quantify it outside its normal/intended use heat treat protocol would be speculative, as most manufacturers use their own treatment protocols... I imagine it might give away some insight to their formula, if they published a specific result from a standardized test.

[PolarisDesu]

From what I know, different kind of elements make a steel corrosion resistant in different ways... Not so much about the heat treatment. Chromium is a good example, it is the most common element used to make stainless steel. But the issue is more complex than that, because for example, carbon stains the steel, so steels with a high amount of carbon are prone to stain, but if we look at the S110V steel, it has a very high amount of carbon, yet because of its other elements like niobium, it is considered corrosion resistant.

I find this alloy compounds very interesting and for sure complex... I wish there could be like some sort of chart were we could easily see some indexes for different steels that are considered "corrosion resistant".

[Bloke]

Lance, is it just a coincidence, ... the LC? :rolleyes:

[SpyderEdgeForever]

Excellent review, Lance! Thank you for the info on this steel.

To the Aussies here: Would a Lc200N blade be great for skinning and butchering water buffaloes and for outdoor work in the bush of the land down under?

[PayneTrain]

From what I know, different kind of elements make a steel corrosion resistant in different ways... Not so much about the heat treatment.

Oh but heat treatment indeed has so much to do with it! Chromium must be free and not in a carbide to provide corrosion resistance. ZDP-189 has 20% Cr, but once hardened, a lot of it is taken up in carbides leaving the steel only semi-stainless. Depending how any steel is processed, it can have a widely varying degree of stain resistance because different elements do different things under different conditions.

[Surfingringo]

Excellent review, Lance! Thank you for the info on this steel.

To the Aussies here: Would a Lc200N blade be great for skinning and butchering water buffaloes and for outdoor work in the bush of the land down under?

Haha, I'm not Aussie but I reckon skinning and butchering a big dirty water buffalo would be a helluva job. I'm a pretty big fan of some of the finer grained steels, but that's a job where I would definitely choose something like s110v over lc200n.

[PolarisDesu]

Oh but heat treatment indeed has so much to do with it! Chromium must be free and not in a carbide to provide corrosion resistance. ZDP-189 has 20% Cr, but once hardened, a lot of it is taken up in carbides leaving the steel only semi-stainless. Depending how any steel is processed, it can have a widely varying degree of stain resistance because different elements do different things under different conditions.

Hmmmm, thanks a lot for this info, metallurgy really gets complicated then.

I guess nobody knows of a chart to compare corrosion resistance among steels?

[PayneTrain]

It is indeed super complicated because of the number of variables involved. For that reason I wouldn't trust any such chart because each sample would have to have so much data identifying it, compositions and heat treatments can be so radically different probably even within the same steel, and so on and so forth that it would be practically impossible to compare apples to apples that way.

I think what you (and probably the rest of us) would really like to see is comparisons of actual knife blades. How does a Spyderco 204P blade compare to a Spyderco VG-10 or a Benchmade 154CM or something like that. At least then we can use it to make actual informed decisions because then we know we're comparing the steels in a form that we're interested in. I don't know of anywhere where there's an actual table like that, but I would love to see someone try to come up with a standardized method of testing his or her knife blades sort of in the way that Ankerson does his edge retention testing. Maybe someday I'll find the time... :)

[Surfingringo]

I think I once made a list of steels and their level of corrosion resistance from best to worst. It was not made based on any formal testing, simply my impressions from using the various steels daily in a saltwater environment. Even I wouldn't be willing to gamble on the accuracy of my ranking but it was probably based on as much actual real world data as anything else you're likely to find. Unfortunately, I have no idea what thread it was in. :o

[PayneTrain]

That would be about as credible a list as I could think of. You have as many corrosive environments to use as any of us, and you're a pretty thoughtful observer. It's a good start to say the least!

Polaris, if you want a good corrosion resistant knife, you can't really do better than H1 or LC200N. They're in some magical class of steels (alloys at least, some people don't even like to call them steel!) that simply can't rust. Outside of these nitrogen based mysteries of of metallurgy, there are a couple good performers, a bunch in the middle, and then the semi stainless, non stainless, and rust magnets. Here's a quick ranking based on my experience with production knives (except one custom and a couple I made myself in the same steel, heat treated differently by the same company). There is pretty much nothing scientific about this list. I'm just occupying myself while my dinner heats up :) :

10: H1, LC200N (based on Surfingringo's report), glass. These things can't rust. Go ahead and try.
9:
8: S110V (really stainless, only managed to get rust spots by leaving joint compound on it to dry, and even then it wiped right off)
7: S90V/CTS-20CP, CTS-XHP, CTS-204P/CPM 20CV/M390
6: VG-10, S30V/S35VN, 440C, Elmax, CTS-B70P, GIN-1, 440A, 12C27, 154CM
5: AUS-8, Cruwear
4: D2, PSF27, Sleipner
3: M4, 1095, 5160
2: Super Blue (rusts in humid weather if not protected)
1: My car (results possibly skewed by New England's liberal use of super-salts on the roads :rolleyes: )

[SpyderEdgeForever]

Oh I just remembered another question I had about lc200n, and this could also apply to H1, I forget if anyone on here has put it through tests: How crack or shock resistant are these two steels when used in a knife blade, as far as when the blade is put under a lot of stress? No significant problems with them, as compared to other steels? Ie, the toughness factor.

Example: If one had to use an Lc200N fixed blade to baton through pieces of wood, or similar work. Obviously, a knife is meant for cutting and not hammering and prying.

And a related thing: What are the "temperature dependent resilience" of this? Example: In very cold climates some steel alloys become brittle quicker than others, like say, how would the temperature effect an H1 or Lc200N blade for someone who was fishing off Northern Alaska, the Arctic, or Canada?

[Bill1170]

I know that H-1 is fantastically tough. Someone once posted a picture of a Salt folder whose blade had been bent almost to 90 degrees in some heavy equipment accident. No cracks.