Steel Junkies: A new laminate S 90V clad with cpm 154 cm FYI

[Ed Schempp]

I'd like to offer some more information on Crucibles new laminate of S90V clad with cpm 154 cm.

Many years ago I was bothering Dick Barber from Crucible Steel to make a USA laminate for the cutlery market. Dick and I exchanged many emails on the topic. (Dick is the guy who designed S 30 V)

As a result of the emails that Dick created a file, a couple of years ago at blade I gave a recommendation for a clad steel using S90V and cpm 154 cm as an example. I referred them to data that they have on high temperature modulus of elasticity that I don't have, to evaluate compatibility.

Crucible made a test billet and I played with some and recommended that they send a sample to Phil Wilson. I just used the Crucible recommended heat treatment. I did substitute a plate quench for a rapid air quench. Crucibles numbers came back with a 5 point spread, 61 at the core and 56 on the clad. Phil had two points difference. I tend to go with Phil's data as he only works in knife geometry and knows more about crucible steel knife applications than any body I know.

Theoretically you should get a blade that in polishable and scratch resistant that is tougher than S90V. This material should be considerably less expensive to grind than solid S 90 V.

To ensure accuracy of placement of the core, smaller billets will be hipped, raising the price of the material.

I like that this is an American made product and the first commercial laminate made in the USA.

Now that they have made this step maybe commercially made USA Damascus won't be to far behind.

Take Care...Ed

[chukar8]

Thanks

[Blade and Flame]

This is very exciting news. Thank you, Ed.

[Cliff Stamp]

Ed,

Why 154CM property wise (not cladding/mating wise). A steel similar to 420J2 would have much higher toughness, ease of machining, grinding, etc. though care would need to be taken to adjust the composition to ensure that the grain was not blown during the high aus-temps if S90V is desired to be at/close to max hardness.

[xceptnl]

This is super news. Thanks Mr. Schempp

[mikerestivo]

Thanks Ed, and keep 'em coming - that is, steel news and knife designs both, man!

[Holland]

great news!!! cant wait

[Evil D]

You used the words "S90V" and "damascus" in the same paragraph, and for a second there I pretty much blacked out from excitement.

[Joshua J.]

Sweet!
More S90V can only be a good thing, and if they have a nice thin core then it wouldn't even be a pain to re-profile.

[bh49]

Ed,

It sound like laminate will be less expensive to grind, but more expensive to make. So blade probably will cost about the same. What will be benefits of laminate over solid S90V for user?
Also what is connection between process of making laminate and Damascus?
Thanks.

[Ed Schempp]

Many of the Spyderco ELU have complained that their 420 J2 laminated blades were getting scratched in use, the clad was too soft. This is not a function problem but a cosmetic problem. The S90V CPM 154 CM recommendation was for folder blades and kitchen use. A lower Carbon clad would be desirable to gain a synergy of the two steels. The other two of the main considerations are processing and target RC numbers. I haven't found high temperature elasticity numbers available. The heat treat numbers can be guesstimated from the heat treating charts. The CPM 154 Cm has much better charpy numbers on the vim/var processed 154 CM. I'm encouraging a slight reduction in the core percentage in future runs of the material.

If I were to design a steel for a large blade the choices would definitely be different. The clad and core would both have a lower Carbon content.

The benefits from cladding has been at the forefront of weapons and tool technology for a long time. I visited the Finch Forge in the Dartmouth Moor and saw that they were cladding blister steel with wrought iron for strength and durability in their production of agricultural tools. I don't know of any example of clad crucible steel but I will bet that it happened. Japanese, Indonesians, Europeans, and many culture came to find this was a very economic process.

The Japanese are very traditional and rarely very from their discipline so their ratio of clad to core is generally in thirds. I like to think with currently available materials and information that we can target application and synergies depending on the choice of material and ratios of core to clad. This product is a stab at that. (Pardon the pun)...Take Care...Ed

[Cliff Stamp]

Many of the Spyderco ELU have complained that their 420 J2 laminated blades were getting scratched in use, the clad was too soft.

Ed,

That I can understand, but that could be solved by simply going to a 5Cr13 steel, 12C27M (as a base platform) would be ideal given the hardness/corrosion resistance ability, but again the exact properties would need to be adjusted.

My concern about 154CM as a cladding is the over engineered nature of 154CM as an exterior cladding when it is in fact a decent high wear primary core material and there is a lot of cost there which isn't producing functional benefits.

[JudasD]

You used the words "S90V" and "damascus" in the same paragraph, and for a second there I pretty much blacked out from excitement.

This pretty much sums it up right here.

JD

[springnr]

"I like that this is an American made product and the first commercial laminate made in the USA."

Sounds like a Native laminate to me ;>)

[Ed Schempp]

Yes, Cliff, you are spot on, I concur with your estimates. The emails I exchanged years ago with Dick Barber included recommendations much like you have given me, except from the line of steel they manufacture. There are some considerations besides function in getting a product to market. The clad had to be in process or in inventory for the experiment to take place. The marketing of 154 CM has been around a long time. There is some synergy between the clad and core. Because of the CPM process the 154 is very nice to work and grind. It polishes very well, better than most stainless knife steels. This laminate should out perform many of it steel competitors for their given applications. This stuff is cool and it is pretty. When you look at Halle Berry do you wonder how fast she runs 100 yards? It is not always about performance it is nice to have a high performance piece of steel in your pocket that you are intrigued and amazed by. If this material sells then maybe the next generation of material will show up down the road. This whole project has availability, convenience, marketability as priorities and increased function trailing behind, yet still advantageous.

Nobody paid me for my recommendation, Spyderco didn't get preference on the initial test billet, all the players got some. This is about opening a horizon that will give us new cooler, and best of higher performance steels, that are made in the USA...Take Care...Ed

[Blerv]

Thanks for your efforts Ed. Glad another of your projects can come to fruition for the betterment of the industry.

I will say the combination of 154cm and S90v seem to peak the interests of everyone from AFI's to mainstream buyers. From a business perspective these steels are well known and it will be exciting to use a Spydie with such a creation.

[Donut]

Ed, thanks for the new steel. I'll be interested to turn a knife made from it into a user.

[Cliff Stamp]

Ed,

Appreciate the frankness as always.

When you look at Halle Berry do you wonder how fast she runs 100 yards?

I was always more of a fan of Prefontaine than the sprinters, don't think she would take him in the mile.

[Chipped Karambit]

At S90v you had my curiousity, and at damascus you had my attention. Sir, this is going to hurt my already empty wallet. Performance with style. And Phil Wilson, he knows some data. Now the next stop is k294 laminate?

[Clip]

When you look at Halle Berry do you wonder how fast she runs 100 yards?

I can guarantee I will now.