What happens to the abrasion resistance of 01

Fred.Rowe

Fred.Rowe

Knifemaker / Craftsman / Service Provider
Joined
May 2, 2004
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As you raise the set temperature for tempering 01, from 500fh.=Hrc57
800fh.=HRC50 1000fh.=HRC42; what happens to the abrasion resistance as the hardness goes down?
If 01 is in the normalized state how much abrasion resistance does it possess compared to hardened 01?

I would appreciate your insight, Fred
 
My thought would be that since the iron would be softer, it would not hold the carbides in place as well, and therefore be less abrasion resistant, but still have more than a simple steel. That is a good question. In the case of 01, Randall runs theirs a bit softer than most custom makers, and yet their knives are still bragged on. You need Kevin or Mete' to get a good answer.
 
In general the matrix , martensite, provides strength preventing the blade from rolling over etc. The carbides provide wear resistance.You really need both for good blade performance .I don't have figures at hand but LRB's comment about the matrix holding the carbides in place would be one of them.
A good example of carbides in a fairly soft matrix is the Talonite blade with it's very high wear resistance but soft matrix [low 50s HRc ].Yes the edges rolled over easily.In an annealed structure where you have very soft ferrite the carbides would have very little support from the ferrite. Good question.
 
LRB said:
My thought would be that since the iron would be softer, it would not hold the carbides in place as well, and therefore be less abrasion resistant, but still have more than a simple steel. That is a good question. In the case of 01, Randall runs theirs a bit softer than most custom makers, and yet their knives are still bragged on. You need Kevin or Mete' to get a good answer.
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mete said:
In general the matrix , martensite, provides strength preventing the blade from rolling over etc. The carbides provide wear resistance.You really need both for good blade performance .I don't have figures at hand but LRB's comment about the matrix holding the carbides in place would be one of them.
A good example of carbides in a fairly soft matrix is the Talonite blade with it's very high wear resistance but soft matrix [low 50s HRc ].Yes the edges rolled over easily.In an annealed structure where you have very soft ferrite the carbides would have very little support from the ferrite. Good question.
Click to expand...

Good explanations, both. The carbides aren't being supported by the soft structure of the matrix and can easily be worn away with friction or abrasion.

This is not a blade shape I am working with; I am adjusting the heat treatment on those 01 grinding clamps I make.
If I were to raise the temper set to 600 or 800 shooting for 53 or even 50 rockwell.
What hardness number should I shoot for to get the most abrasion resistance with very little chance the clamp will break. The left three inches as you view the pic is hardened. I need that section that rides against the belt to not abrade. Not wear away. I can't make it so hard that it will be brittle and break when the bolt is tighten down against a 1/4 inch blade blank.

What hardness do you believe is the best trade off; brittleness to abrasion resistance in this situation? 50hrc? 43hrc? I'm at 57 now and get some breakage along the hardened clamping fingers. I am working on my 400+ clamp and run good control on my heat cycling.


Regards, Fred

DSC00559.JPG
 
50HRc should do it , give it a try. It would be nice if you had a 800F salt pot and differentially temper the piece.
 
it would be another step or 2 but what if you reused old lathe carbide cutters and jsut drilled and tapped for them as you "grind face" im betting a tool and die shop would have plenty used up and they would be fairly small then you would not have ot worry about harness
 
butcher_block said:
it would be another step or 2 but what if you reused old lathe carbide cutters and jsut drilled and tapped for them as you "grind face" im betting a tool and die shop would have plenty used up and they would be fairly small then you would not have ot worry about harness
Click to expand...

Morning Butch!

That might be an option, but as you say it would add steps to the process. There is quite a bit of labor goes into each clamp, with the slotting and drilling and then tapping. The heat cycling with two normalizing and then hardening followed by to tempering cycles adds up. I ran a tempering cycle at 800 this morning on a couple of the clamps that were at 57 Hrc. I will be testing those this afternoon to see how the measure up with the 50 hrc.

Thanks for posting, FRed
 
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