Spyderco Forums

Cliff - in the hardened state, the YM is similar to titanium, and we haven't had any issues with it yet. In fact the low YM coupled with the high hardness form what is termed a high "Modell" number - and that's what gives SM-100 such great wear resistance. It's Modell number is twice that of a steel such as 440C or M-50. NASA was so intrigued by this that they put out a couple of papers on just this subject.

Hopefully we will get to see a spyderco released with an SM-100 blade someday in the future.

i dont care what model or what colour the knife is, im getting it if it comes in sm100.... but a Ti para or Ti Military with rust proof hardware and Ti clip - combined with sm100 would make a good dive knife

Sounds interesting.

Cliff Stamp wrote:The extremely low YM does not pose a concern?

Cliff, in general terms, how does Young's Modulus relate to a blade's properties in use?

razorsharp wrote:i dont care what model or what colour the knife is, im getting it if it comes in sm100.... but a Ti para or Ti Military with rust proof hardware and Ti clip - combined with sm100 would make a good dive knife

+1 i would be perfectly happy with a Mule team!

Popsickle wrote:+1 i would be perfectly happy with a Mule team!

****, id buy a ladybug in it

Hi Eric,

We'll need a sample piece at least 2" x 4" for testing. Duane called me on the material a while back and I said I was in, but haven't received anything yet. What "Blade" type testing have you done?

Hey Cliff,

As Xavierdoc mentioned, we need a tutorial on YM. Have you had a chance to play with this stuff?

sal

sm-100 wrote:Cliff - in the hardened state, the YM is similar to titanium, and we haven't had any issues with it yet. In fact the low YM coupled with the high hardness form what is termed a high "Modell" number - and that's what gives SM-100 such great wear resistance.

I am familiar with Oberle's work, however the ability to easily distort only translates to high wear resistance when it reduces localized pressures and prevents fracture from surface to surface contacts. There is nothing in Oberle's work, or the reports from DellaCorte et. al. (NASA) which would even imply this would lead to greater wear in sharpened edges, in fact the exact opposite is clear from the Aug. 2011 paper. In that DellaCorte et. al. noted for example that the samples they had contained large void chains up to 150 microns in length. This if present in an sharpened edge would obviously lead to huge blowouts similar to the surface spalling they saw in the samples, again attributed to the large voids.

Beyond the voids, the low YM would cause the edge to go out of compression loading and into lateral loading in the cutting at a much smaller cutting load than steels. As lateral loading has a much lower fail point than compression, this would mean the edges would have to be significantly thickened to compensate for the much lower YM and thus lower cutting ability, ease of sharpening, etc. .

It's Modell number is twice that of a steel such as 440C or M-50. NASA was so intrigued by this that they put out a couple of papers on just this subject.

Yes, for bearing and similar, the properties are not related, it would be like comparing the tires from a tractor and then implying that praise/success there could imply translatable implications to bicycle tires. While there are similar design constraints, they are both tires, they are fairly different as well so making the jump from one to the other is a bit of a stretch without carefully considering the actual difference in goals/loads.

sal wrote:Have you had a chance to play with this stuff?

No, I have used Ti in many forms, Stellite (in all of its forms, forged, Talonite, Boye's cast), etc. and am familiar with the properties. The problem with making the jump to knives is that you have to consider the properties that knives needs. For example SM-100 records much higher on a Brinell than a Rockwell tester than steel, even if it tests lower on a HRC reading it can test higher on a Brinell. You can not however use this very high Brinell reading to imply that knife edges would be more impact resistant / durable because the mechanism that allows this (the low YM causes the impact area to expand as the Brinell uses a ball so the area expands rapidly with depth and thus the pressure drops off) will not happen in edge contacts.

I would be curious of how it would perform in a knife designed to cut things well, even assuming that they have eliminated the segregation and voiding (P/M would do that easily) I don't see anything in the properties that would jump out and claim a great knife material. But experimentation would always be in order assuming the time/money is there.

Sal - all our scientific testing has been geared toward bearing and gearing type tests since that's where the material was originally developed for. We have seen qualitative tests done by Duane and Elliot (i.e. chopping wood, smashing it into a steel pole, etc.), and I think Les George has done similar type abuse tests, but we don't have any sort of quantitative data yet. We'd love to work with you on this aspect as well if you are willing. We have some thoughts here that we can discuss at Blade.

Really looking forward to meeting you!

sm-100 wrote:...we don't have any sort of quantitative data yet.

Are HT'ed bars available for purchase?

Thank you Cliff.

Sal, Any news on this stuff making its way into spyderco? I've been carrying a Jeremy Robertson el patron custom in SM-100 and have to say I love the stuff!

We've done some testing on the test mule and we're working with SM-100 to deetermine optimal geometries. I think the high cost would make a Mule Team very expensive. My preference would be for a short run of a simple folder like the UK.

sal

sal wrote:We've done some testing on the test mule and we're working with SM-100 to deetermine optimal geometries. I think the high cost would make a Mule Team very expensive. My preference would be for a short run of a simple folder like the UK.

sal

hmmmm, UKPK .... would be a good idea :D . Personally id love to see it in a locking folder ... maybe a native 5, para2 , millie, ppt.... or in models where it wont happen like chaparral and sage haha. But im so desperate to try it i would get a UKPK .

Yes, a g10 UKPK would be great. Please, please, please! :)

An sm100 para or manix 2 Xl would be awesome

id prefer a locking folder as well, para2 would be ideal!

I like the idea of a UKPK lightweight in the steel. On that note, more lightweight models for steel testing platforms.

It's economical for the ELU and isn't limited by legislation. Ultimately more testers and more honest feedback.

sal wrote:We've done some testing on the test mule and we're working with SM-100 to deetermine optimal geometries. I think the high cost would make a Mule Team very expensive. My preference would be for a short run of a simple folder like the UK.

sal

Thanks for the response sal! I believe what ever it comes out in people will buy it. keep us posted as this would be huge for spyderco fans being able to get a production knife in this steel. So far as I can tell about this steel it is very durable, holds a fine edge, and gets very sharp.

Para Mil 2 PLEASE!!!!!!!!


:)