Composite Blade Leek


PDA






Striker
March 6, 2008, 03:42 PM
Just noticed that New Graham has a Leek with a composite "Sandvik 13C26/CPM-D2" blade.

http://www.newgraham.com/detail.aspx?ID=44884

Anybody have any experience with this knife? I'm wondering what, if any, is the advantage of a composite blade of this type.

If you enjoyed reading about "Composite Blade Leek" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
hso
March 6, 2008, 06:53 PM
It's purty.

The standard reason for a laminate (the blade isn't really a composite) is to provide one characteristic in one area and another characteristic in a second area. In this case, cutting capability with the CPM-D2 and rust resistance with the Sandvik.

I have been told by some custom knife makers that the CPM-D2 is impressive stuff for cutting performance.

JackalJones
March 8, 2008, 06:29 PM
I have one of the Kershaw Tyrades with that style composite blade.
It is 154CM steel with a CPM D2 cutting edge. It is really sharp.
At the price point of the composite Leek, I can't pass it up.

From what I understand, the 13C26 steel is used to keep costs
down versus the entire blade being made of D2.

steve

rbmcmjr
March 10, 2008, 11:11 PM
The standard reason for a laminate (the blade isn't really a composite) is to provide one characteristic in one area and another characteristic in a second area. In this case, cutting capability with the CPM-D2 and rust resistance with the Sandvik.

hso,

What do you mean by this? What are you calling a composite? This blade is NOT a laminate in the traditional sense. As I understand it, the D2 and 154 are assembled (welded) together and then slices of the composite block are machined into blades.

My Tyrade uses the same construction:

http://i20.photobucket.com/albums/b240/rbmcmjr/tyrade1.jpg

hso
March 11, 2008, 02:06 PM
To my thinking -

Composites are a combination of a matrix material and other materials that create a new material with properties different from the original components. That new composite material then can be made into items.

Mud+straw=brick, cement+aggregate=concrete, phenolic resin+cotton cloth=micarta, epoxy+glass fiber=fiberglass, acrylic+alumina mineral powder=corian, nylon+glass fiber=Zytel, epoxy+carbon fiber=carbon fiber composite

Laminates are layers of different materials adhered together. Laminated steels are 2 or more layers of different steel welded together. A new material isn't formed, but the beneficial properties of one material are used to offset the less beneficial properties of the other. Laminated steels are usually protecting a harder steel with poorer rust resistance or brittleness with tougher or more corrosion resistant steels to offset the "weakness" of the edge material. Sometimes it's just to offset the high price in a world of ever higher spiraling metals prices.

A sandwich of d2 between layers of 154CM would be a laminate. The fact that the billet is ground so that the d2 is the edge is a method that's been used with other blades in the past (notably the Cold Steel "San Mai" blades and a long tradition of Scandinavian blades as well as Japanese swords) and is the purpose of laminating the steels together.http://www.bladeforums.com/forums/showthread.php?t=339919 http://outdoors-magazine.com/spip.php?article36

There have been some clever people that have jig-saw puzzled highly desirable expensive blade steel along the edge with lower performing steel in the bulk of the blade. Those are neither a laminate or a composite material, but the blade is called a composite structure. What I thought was just a laminate with an interesting grind revealing the interface of the layer actually appears to be a composite structure with the Tyrade and new Leeks. The blade isn't a composite material, but the blade is a composite structure (sloppy terminology, but that's just the way the terms go) of CPM D2 keyed and then fused to the 154CM body of the blade.

Pattern welded steel makers who make their steel in a can (powder) use solid shapes set in the powder and then forge weld the whole thing. Kinda looks like something like this may be going on, but I'm just guessing. They may actually cut the two interlocking shapes of the CPM D2 and the 154CM and then forge weld them together, but it would be easier in one sense to cut the complex keyed face of a billet of 154CM and then use the CPM process to form the D2 onto the end of the billet.

Now I gotta go and ask Ken.

hso
March 12, 2008, 03:25 PM
Here's what Ken sent to me -
The CPM-154 is laser cut, The D-2 is EDM cut and then they are pressed together. A copper solder is applied to the joint and then it is heat treated . During H/T the solder fills any void and leaves an thin ribbon to highlight the seam

So, they do cut the two pieces and key them together instead of what I thought to be the easier powder metallurgy approach.

SDC
March 12, 2008, 03:50 PM
Very interesting; thanks for the legwork, hso.

rbmcmjr
March 13, 2008, 12:35 AM
I found a cool picture of the pieces:

http://i20.photobucket.com/albums/b240/rbmcmjr/Wire3.jpg

SDC
March 13, 2008, 10:26 AM
That is wild; I may have to get one of these just for the "Neat!" factor.

If you enjoyed reading about "Composite Blade Leek" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!