Choice of abrasives, time on the abrasive, pressure on the abrasive, many factors can easily favor chromium carbide vs vanadium carbide steels as the latter is much harder. For example, simply use an abrasive which is harder than chromium carbide but softer than vanadium carbide and the high vanadium steels will not have equal sharpness and have much lower edge retention.
All the steels were sharpened on 600 grit diamond belts, with a mechanical fixture used to establish sharpening angle. The wire edge, or burr was then removed on a cardboard wheel with chromium oxide compound. No games were intended to be played.
For a knife cutting through biological materials (meat, hair, hide, hemp) I personally believe that the force required to initiate cutting is more important than the amount of material cut per stroke on a CATRA ERT machine. In particular, steels containing large carbides lose their sharp edge, but continue to cut on a CATRA ERT tester because the carbide particles act like teeth on a rod saw, and continue to cut under the high normal force, even though the knife isn't even close to shaving.
I like to cut with a knife that's shaving sharp. The CATRA REST tester is used to test razor edges. Sure, it's a push test, but so is a shaving test.
The presentation presented at Tejon Ranch is available at this link:
http://www.et.byu.edu/~sorensen/Tejon%20Presentation.pdf
A preprint of the technical paper describing the Friction Forging technology as applied to D2 is found here:
http://www.et.byu.edu/~sorensen/TMS%202007%20D2%20Processing.pdf
If you'd like raw data, I'd be happy to provide it.
I won't claim to be perfect, but we certainly haven't monkeyed with the data to try to get it to support a claim of improved performance. We've worked to make a knife with improved performance, and let the data be whatever it turns out to be.
I repeat, every steel that was tested, including the FFD2, was sharpened with the same procedure, which was to sharpen the best way we knew how for a production knife. None of the steels, including the FFD2, was tested to determine an optimum edge geometry for that steel. So if different steels have different optimum edge geometries, the tests didn't control for that. But the test was equivalent for all steels. We picked a geometry, sharpened to that geometry, and tested for performance.
Before somebody thinks we're trying to hide something, I'll point out that we didn't use CATRA media to wear the edge, we used hemp rope. But again, all knives were subjected to the same tests.
I'm happy to provide any information I can to help you do your own analyses.
Carl Sorensen
