LC200N vs N680 vs X15TN

[Doc Dan]

https://www.zknives.com/knives/steels/s ... hrn=1&gm=0

Somebody help me understand why LC200N is a better choice than the other two.

More nitrogen

That is a good point and I don't know why I didn't think about that. N would, in the right mix, make it more corrosion resistant, for sure.

Well, that's what makes LC200N so "exotic"

It is difficult to get high volumes of nitrogen into steel.

So, that should immediately standout as something special.

0.10-0.20% range of Nitrogen (N) is the limit with most conventional methods.


The 0.5-06% N requires a special process that increases cost.

PESR rather than ESR.


(Pressurized Electro Slag Remelting)

This is still cheaper than the nitrided powder technique used for the " diffusion alloying" method needed for Vanax which is extremely expensive but can achieve even higher nitrogen than the PESR used for LC200N.

That why Vanax is so cost prohibitive.



For LC200N, the additional Nitrogen over N680/X15TN not only boosts the corrision resistance in itself but also helps increase the working hardness and wear resistance over N680/X15TN.

LC200N does this by putting more dissolved, interstitial nitrogen into solution with austenite during heat treatment for more diffusionless transformation into nitrogen rich martensite upon cooling. The increased nitrogen also creates more of the harder M2X chromium nitrides which are harder than M7C3 chromium carbides.

After careful heat treatment, I can achieve a working hardness of 61-62rc with LC200N, this is extremely impressive for this material.

The consequence to hardness HRC comes from the increased chromium in solution; this severely limits the achievable hardness HRC regardless of the improvement described above from the higher nitrogen.

It's the same reason Vanax is so limited in higher hardness (60-61rc)

This has always been the severe trade-off for the highest corrosion resistant steels; the additional chromium in solution severely limits the hardness.

That's why another steel, MagnaCut, is so impressive since it achieves a high corrosion resistance without the hardness HRC capped at ~60rc due to limiting excessive chromium in solution yet, achieving high corrosion resistance through elimination of chromium carbides.

It's a brilliant and innovative design.


In the end, N680 and X15TN simply do not have the "firepower" in the chemistry to match the hardness and wear resistance to make them as exciting as LC200N.

Neither N680 nor X15TN are something I'd use in a premium custom, they don't have the "horsepower".



So, in simple terms, to answer the original question.


"More Nitrogen"

Hey, thanks. That was easy to understand, even for me. Maybe you should write a book that explains things in simple language.

[cabfrank]

That does make it more understandable. I know I plan on getting some LC200N one of these days. As much as I love H1 I'm curious to give it a go. The others haven't been on my radar.

[Doc Dan]

Still waiting on the Dragonfly 2 LC200N.