Knife News Report: Nitrogen-based Steels

[SpyderNut]

Just received an interesting article from Knife News today regarding nitrogen-based steels and thought you all might enjoy it:

Are We Entering the Era of Nitrogen-Based Blade Steels?
March 19, 2018

With the advent of particle metallurgy, nitrogen-based steels have become a growing presence in the knife world. And according to Elliot Williamson, Founder of Ferrum Forge Knife Works, one nitrogen-based steel in particular, CTS-BD1N, has the potential to become as ubiquitous as VG-10 or S35VN.

Williamson, who has worked with nitrogen-based steels for years, says the category brings significant advantages over more traditional chemical compositions. Nitrogen molecules being one third the size of chromium results in a more refined grain structure, resulting in a blade that takes a finer edge and that is less susceptible to chipping.

The presence of nitrogen also allows for less chromium to be used in general while still maintaining or even improving a steel’s stain resistance. In a DIN 50021 salt spray test, where samples are sprayed with a saltwater solution and left to sit for a set time to gauge their corrosion resistance, Böhler-Uddholm’s N360 nitrogen steel proved more rust resistant than 440C, even though 440C contains more chromium than N360. “Chromium is a necessary evil in martensitic stainless steel, but nitrogen stainless steels do seem to mitigate some of its drawbacks” Williamson concludes.

Williamson tells us among the current crop of nitrogen steels N360 and ETK’s Z-Finit are comparable to S7 tool steel, albeit with extremely heightened stain resistance, and edge retention on par with 154-CM. But he tells us Carpenter’s CTS-BD1N holds the potential to achieve stardom as the go-to performer of the production knife world. It costs about the same as VG-10 or N690, with a better mix of wear resistance, corrosion resistance, and sharpenability. These qualities make it an easy choice for anyone looking for the best price-to-performance ratio. “I think this could be the steel that changes things in the industry,” Williamson says.

Williamson does highlight one practical drawback which could get in the way of the widespread adoption of the blade material. “My major concern about BD1N is whether or not Carpenter will be able to keep enough of it supplied,” he tells us. Cold Steel recently announced they had to ditch Carpenter’s CTS-XHP as their standard blade material because the company couldn’t maintain a reliable stream.

Despite the risk, Sal Glesser has already revealed that Spyderco’s Chinese OEM will likely start phasing in CTS-BD1N to replace the BD1 on models like the Polestar and Raven 2. If others follow, BD1N could represent a new watermark for budget-friendly steel performance. “It’s really going to come down to how many companies pick it up and promote it, how many are willing to put real marketing dollars behind it.”

(Link: http://knifenews.com/are-we-entering-th ... de-steels/)

[ZMW]

I think so! It makes sense with the benefits of H1, LC200N, and I am sure there will be newer and better ones in the future

[The Meat man]

I for one am looking forward to these increasing options.

[p_atrick]

Might be worth posting this over in the thread about steels that could replace VG-10.

[Surfingringo]

A couple of years ago when I first heard about bd1n, I had a chance to try it in a test knife that Phil Wilson made for me. I tested it mainly for corrosion resistance and then passed it along to Jim to test for edge retention. The example I tested showed good corrosion resistance but nothing extraordinary like lc200n/H1/Vanax. My knife exhibits corrosion resistance on par with s90v. In fact I tested it side by side with s90v and they were very similar. Wear resistance was pretty high (similar to or a bit better than s30v class I would say) but I would take a fully corrosion proof steel like Vanax over bd1n any day. I think one of the advantages of bd1n is it is pretty affordable for the set of characteristics it delivers. I agree with the article that nitrogen steels could lead the way into the future but I think they are overhyping bd1n as the creme de la creme. It's a good steel and I'm looking forward to having access to it (especially if it's offered as an upgraded steel in some affordable spydies) but for my money there are already more interesting Nitrogen steels out there and there are certainly more to come.

[Surfingringo]

One other thing. From an performance/wear resistance perspective, I found BD1n to be a huge step up from bd1. Like two completely different steels. In my opinion, the gap between bd1 and bd1n is similar to the gap between 8cr13 and s30v. If that change were actually made in affordable knives like the polestar and raven 2 then it would bump those knives into a completely new performance category.

[Bloke]

... The example I tested showed good corrosion resistance but nothing extraordinary like lc200n/H1/Vanax. My knife exhibits corrosion resistance on par with s90v. In fact I tested it side by side with s90v and they were very similar.

Interesting read Michael. :)

I have no experience with BD1N but reading Lance’s observations I’m a little sceptical about BD1N’s corrosion resistance.

The pic below is of my Sprig (S90V). I brain spiked a fish, sloshed the knife in the surf and put it back in the sheath. Undoubtedly there must have been some residual blood left on the blade but this was the result after no more than three hours on a fairly hot day and that was after a clean with a green dish scourer. :eek:

[sal]

Hitachi makes a steel called Gingami 1. It has proven to be effective, to a point, in resisting corrosion. Better than many other steels. We've used it quite a bit.

We helped Carpenter get into the knife industry by testing steels for them with our CATRA machine and giving them results and our opinions. This was over a two year period. We did many tests. When they began introducing their CTS steels, they asked me if there was something they could do for me to show appreciation for our efforts. I asked them if they would make, for me, a version of Hitachi's Gingami 1 and even tweak it if they could. I thought that it could be an effective blade steel. Carpenter made the steel. They called it BD1. Then they tweaked it and called it BD1N.

I agree with Lance that it is a good steel, with better than average corrosion resistance, but the "N" in BD1N is an enhancement, rather than a carbon replacement.

sal

[SpyderEdgeForever]

One other thing. From an performance/wear resistance perspective, I found BD1n to be a huge step up from bd1. Like two completely different steels. In my opinion, the gap between bd1 and bd1n is similar to the gap between 8cr13 and s30v. If that change were actually made in affordable knives like the polestar and raven 2 then it would bump those knives into a completely new performance category.

Lance, thank you for this analysis: I have a question for you then: In considering a purchase of the Byrd Raven 2 with the BD1 blade, would it possibly be a good idea to wait until the BD1N version is available, since as you said, it is different than the standard BD1 stainless?

[SpyderEdgeForever]

Essentially then, BD1N would be considered to be an "Economy Nitrogen Stainless Steel" without being revolutionary in the sense of H1 and Lc200N, correct?

[Surfingringo]

Essentially then, BD1N would be considered to be an "Economy Nitrogen Stainless Steel" without being revolutionary in the sense of H1 and Lc200N, correct?

I think it depends on what you believe makes these steels special. To me, it's all about the corrosion resistance. I mean, if you took the corrosion proof characteristic away from lc200n you would be left with a steel that is a solid performer but nothing revolutionary when compared to all the other steels we have access too. So for me it's the corrosion proof aspect of the nitrogen steels that make them revolutionary. As I said earlier though, bd1n is a really nice steel and I think it would be a big performance jump if could be offered in some of the "budget line". It would give folks the chance to own a knife like the Raven 2 with "s30v like" performance (and better corrosion resistance). I'm generalizing with that statement but I think it's a relatively fair comparison.

[curlyhairedboy]

Nice to see metallurgy making the news.

From a materials perspective, I'm not sure the article hits the right technical notes, but it's humming along to the melody :P

I'll quote myself from an earlier thread where I did a brief literature review:

As for H1's superior corrosion resistance - there are several ideas about how the nitrogen helps. First, most of the corrosion resistance is due to the high chromium content (14% if my memory serves). The chromium oxidizes on exposed surfaces and forms a protective layer - a durable, invisible patina.

One theory has the nitrogen in the lattice concentrating near the surface, aiding the chromium oxide layer
One theory has the nitrogen converting to NH4 ion when exposed in salty solutions, changing the chemistry near the surface to be less favorable to corrosion
One theory has the nitrogen - being more evenly distributed in the lattice - preventing the kind of intergranular corrosion common with carbide formation at grain boundaries.

There are more ideas out there, and the reality is probably one or more of them.

Bolded part is the most revelant to the current conversation.

[guywithopinion]

This steel is in production with Spyderco currently, right? I've seen people post pictures of the UKPK with the blade marked "CTS BD1N".

[Deadboxhero]

Hitachi makes a steel called Gingami 1. It has proven to be effective, to a point, in resisting corrosion. Better than many other steels. We've used it quite a bit.

We helped Carpenter get into the knife industry by testing steels for them with our CATRA machine and giving them results and our opinions. This was over a two year period. We did many tests. When they began introducing their CTS steels, they asked me if there was something they could do for me to show appreciation for our efforts. I asked them if they would make, for me, a version of Hitachi's Gingami 1 and even tweak it if they could. I thought that it could be an effective blade steel. Carpenter made the steel. They called it BD1. Then they tweaked it and called it BD1N.

I agree with Lance that it is a good steel, with better than average corrosion resistance, but the "N" in BD1N is an enhancement, rather than a carbon replacement.

sal

I really really enjoy BD1N

I think that steels the use nitrogen as a enhancer and not a replacement are a game changer.

That's why I was excited about Vancron40.
BD1N is great but it's a curiosity of what happens when you blend a high alloy tool steel with a Nitrogen enhancement.

I haven't been blown away by edge performance on the Nitrogen steels that replace carbon. So I feel the future is in steels that take advantage of having both.

Maybe in 10 years we can get something like a S90VN with a Nitrogen boost and higher working hardness.
That would be great.

[dj moonbat]

I haven't been blown away by edge performance on the Nitrogen steels that replace carbon. So I feel the future is in steels that take advantage of having both.

Maybe in 10 years we can get something like a S90VN with a Nitrogen boost and higher working hardness.
That would be great.

Cliff wrote a post a couple weeks ago about what the addition of nitrogen allows in traditional martensitic steels. Typically thorough. It got me thinking exactly what you've said here.

[TomAiello]

What Spyderco knives are currently using BD1N? Does anyone have a list?

[p_atrick]

I haven't been blown away by edge performance on the Nitrogen steels that replace carbon. So I feel the future is in steels that take advantage of having both.

Maybe in 10 years we can get something like a S90VN with a Nitrogen boost and higher working hardness.
That would be great.

Cliff wrote a post a couple weeks ago about what the addition of nitrogen allows in traditional martensitic steels. Typically thorough. It got me thinking exactly what you've said here.

Where can I find this post? Does he have a website or is it on a forum? Thanks.

[ThePeacent]

I've liked CTS-BD1 so far (3 knives), and H1 is my favorite steel...imagine combining the two and you essentially have BD1N. :rolleyes:
Very excited to see this steel on budget line!!

[mjdragonfly]

would steels like 52100, V-toku2 and ZDP-189 be candidates for addition of nitrogen into the mix?

[vivi]

Hitachi makes a steel called Gingami 1. It has proven to be effective, to a point, in resisting corrosion. Better than many other steels. We've used it quite a bit.

We helped Carpenter get into the knife industry by testing steels for them with our CATRA machine and giving them results and our opinions. This was over a two year period. We did many tests. When they began introducing their CTS steels, they asked me if there was something they could do for me to show appreciation for our efforts. I asked them if they would make, for me, a version of Hitachi's Gingami 1 and even tweak it if they could. I thought that it could be an effective blade steel. Carpenter made the steel. They called it BD1. Then they tweaked it and called it BD1N.

I agree with Lance that it is a good steel, with better than average corrosion resistance, but the "N" in BD1N is an enhancement, rather than a carbon replacement.

sal

Thanks for the info Sal.

FWIW BD1 is currently one of my favorite steels. It sharpens extremely well, resists corrosion very well, and holds an edge well. The edge holding on my Ronin 2 and Voyager is close to VG10. I'd definitely be interested in seeing this nitrogen version used in some fixed blades and full sized folders!