60-NiTiNOL - Hype or...

T

TempusExMachina

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Nov 30, 2012
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I'm wondering if all the hype surrounding 60-NiTiNOL (SM-100) is substantiated by actual comparison testing. This nickel (60%) - titanium (40%) alloy is supposed to be corrosion proof (NASA's claim), has around 62 HRC, non-magnetic, 20% lighter than most steels, and has shape memory. Yet, there is absolutely no video comparison testing with any super steels on the internet, let alone a stand alone video performance test. I know it's pricey, but if it's this good, a video test should be made...

Here's the manufacturer's info page: http://www.summitmaterials.com/sm-100/knives/

If anyone has any real life performance examples on the internet, preferably on video, please let me know.
 
I think there's at least hype if not some BS... From the sound of it, it should make a great chopper... Why waste such strength and toughness on a mere folder?!
 
Young's Modulus is very low for it, it will deform more under stress than comparable steels according to that data. Looks interesting though!
 
Skimo said:
I think there's at least hype if not some BS... From the sound of it, it should make a great chopper... Why waste such strength and toughness on a mere folder?!
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Good luck finding a chopper-sized chunk of SM-100 and the price would be out of reach for all but a few of us, but otherwise it's a good idea. ;)

It is practically hardenable titanium. Aside from the price, whats not to like?
I have high hopes for the future of SM-100 but I would also like to see some reputable tests and a larger user-base before I decide to try it.

The green forum has more information on 60 NiTiNOL PM, but not much more.
 
Nullity said:
Good luck finding a chopper-sized chunk of SM-100 and the price would be out of reach for all but a few of us, but otherwise it's a good idea. ;)

It is practically hardenable titanium. Aside from the price, whats not to like?
I have high hopes for the future of SM-100 but I would also like to see some reputable tests and a larger user-base before I decide to try it.

The green forum has more information on 60 NiTiNOL PM, but not much more.
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Hey! Welcome back Nunu! :D
 
It has apparently been compared to Elmax for edge retention, which isn't bad. It is a bit difficult to reconcile the performance for the price, as there are steels that outlast Elmax for edge retention, and to have the toughness come into play for a large working knife means paying a huge sum for the raw material and the grinding. For a smaller knife where there isn't impact and one might want to maximize wear resistance, M4, S90V, 10V, etc might be better choices for the cost. For large knives, H1 has toughness and lack of rusting to compare favorably. Also, as bpeezer said, the YM is really low, so who knows if at the cutting edge there will actually be any decent working life. The blade as a whole may survive impacts and flex, but the edge may deform too easily.

But, we may find that SM-100's blend of properties is just what some people are looking for, and they will pay for the performance willingly. I don't know that I have enough personal interest, but I wouldn't mind working on arranging tests.
 
As a lazy person who dislikes slippery, oil-drenched sharp things and enjoys resiliant tools, the corrosion-proof attribute has me most interested.
A corrosion-proof Elmax... Yes please. :)

Now I've got to Google "Young's Modulus"... (and howdy singularity :D)
 
I read a report somewhere that said it had porosity issues, with pores much larger than the carbides in p/m steels, big enough even to cause spalling. Not a good sign for thin (1 micron and smaller) edges. Sounds like a lot of hype to me, at least for blade steels.
 
Nullity said:
As a lazy person who dislikes slippery, oil-drenched sharp things and enjoys resiliant tools, the corrosion-proof attribute has me most interested.
A corrosion-proof Elmax... Yes please. :)

Now I've got to Google "Young's Modulus"... (and howdy singularity :D)
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If you look at a Stress vs. Strain curve, Young's Modulus is the slope of the line in the elastic portion of strain (the slope of the straight part). It tells you how much it will deform (strain) for how much force you put on it (stress).
 
ah, that I believe is one of their selling points. The PM version, SM-100, claims better properties because the process aids in wear resistance and homogeneity.
 
Apparently, SM-100 is the PM version that's more refined.

If it helps at all, here's a snapshot of the microstructure.

SM-100-microstructure.jpg
 
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If SM-100 has a low Young's Modulus, then couldn't it just mean that there is a relatively large change in the metal's length (given its super elasticity) when X force is applied that causes the metal to lengthen? So, if a "large" force is applied to the metal, but a "larger" change in length of the metal occurs, could the Young's Modulus be misleading when compared to steels?
 
In flexing, the inside of the bend is compressed and the outside is under tension. So if we are talking about a thin knife edge being subjected to lateral forces, the low YM means it could deflect really easily while hard cutting and may permanently deform. Then there is the 'sharpened prybar' aspect if people want to wail on this material due to its impact toughness (that I don't see on the site?) The memory aspect could fix it, if you were gonna throw your knife in the oven every time it bent, or just use a material requiring more force to bend. But I don't know, never tried the stuff.
 
hardheart said:
In flexing, the inside of the bend is compressed and the outside is under tension. So if we are talking about a thin knife edge being subjected to lateral forces, the low YM means it could deflect really easily while hard cutting and may permanently deform. Then there is the 'sharpened prybar' aspect if people want to wail on this material due to its impact toughness (that I don't see on the site?) The memory aspect could fix it, if you were gonna throw your knife in the oven every time it bent, or just use a material requiring more force to bend. But I don't know, never tried the stuff.
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Yeah, that would be my concern spot on. If it's fixable through its shape memory, then it may not be a problem though a hassle. I hope someone can bring light to this with real world performance testing / comparisons.
 
Since Young's Modulus is the slope of the elastic region, it is also the slope of the stress/strain curve during unloading. This is a big part of "shape memory" because a material with a lower Young's Modulus will spring back far more than a material with a high Young's Modulus.

The material will bend more easily than others, but it will "spring back" more afterwards. And I never though I would use my materials analysis classes in real life :D
 
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