Ranking of Steels in Categories based on Edge Retention cutting 5/8" rope

Edge pro. Stones that came with it. Jim has recommended some upgraded stones, but I haven't tried them out. I am guessing I stopped at 600 or 1000 grit by the looks of that bevel.
 
What is guestimate(or actual) this 'very very fine' carbide diameter in micron? My wag is 1.5-2.5um, whereas s90v/s110v ~3-5um.

A laminated 4v at same hrc as laminated hap40 should have similar over all performance. 4v has a tiny advantage with wear resistant but slightly behind ease to achieve high keenness level. M4 probably exaggerate this different a little bit more. I agree with you - impact toughness for these blades are very poor. However it won't be an issue, if the user exercise the blade strength and avoid impacts(exceed inherent toughness).

daberti said:
Surf,
a real advantage of CPM-M4, and other W+V (and very small percentage of Moly carbides if any) steels like HAP40 and BU equiparable grades is that carbide size it is very very fine. S90V and S110V have bigger indeed ones, even bigger has S125V.
Where AISI 3:2 + Co does NOT get me in is that to deliver a noticeable advantage in edge retention compared against CPM-M4 (20%more) it needs to be very close to its upper HRC range, having very poor toughness. As I've already said a well HTd K390 will easily outperform it under ANY aspect, with just a hair bit more effort in touching up.
Regrinding is another story ;)
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Actually i.e. 440B/C or D2 have carbides in excess of 100um, lets say between 100 and 200um.
Finest hard particles are the Nitrides in Vanax, 0.7um.
Cr carbides in S90V could be in between 20 and 50um, whereas V carbides will be smaller (probably 5-20um) and V carbides in CPM-3V will be noticeably smaller than these.
W carbides can go as low as 2um.
Of course in an ideal world, ideal HT...

And yes, CPM-M4 and equivalents are very very respected in my personal list, as with slightly more V carbides than 3V and some W carbides for a grand total of 12.6%, will show very fine carbide size, probably in the 3-4um and 2-3um respectively.
 
nccole said:
Thanks Jim. It's a little bit lower than I was hoping but still respectable.
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mmmhhh, less than half of what it could/should deliver with that TBE whilst still staying in a reasonably safe zone though (i.e. 65HRC)

Thanks Jim !
 
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daberti said:
mmmhhh, half of what it could/should deliver with that TBE whilst still staying in a reasonably safe zone though (i.e. 65HRC)

Thanks Jim !
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I don't think it was anything near 65 HRC, my SIC stones ate it like butter, even when making the bevels the same on both sides of blade.

I didn't use anything lower than 320 grit.

I can guess what it I think it was, but I won't. ;)
 
Neither will I [emoji106]
Thanks again Jim

EDIT
Apart from being this blade another OF (Oven Friendly :D :thumbdn: :rolleyes: ) Award Winner candidate, these steels like CPM-M4 M3:2 and alike are rebevellicious even when at the HRC they should be, for the reasons explained above.
I can confidently take 'em in the wild knowing I'll be able to address any edge problem with minimal equipment.

Back to this very knife, the steel has Cr7C3 carbides in the Annealed state and I'm pretty confident it will have them to some extent even in its current state, so its corrosion resistance would be ....well :thumbdn::thumbdn:

One more reason to me to steer away from current Spyderco line.


Dan
 
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daberti said:
Neither will I [emoji106]��
Thanks again Jim

EDIT
Apart from being this blade another OF (Oven Friendly :D :thumbdn: :rolleyes: ) Award Winner candidate, these steels like CPM-M4 M3:2 and alike are rebevellicious even when at the HRC they should be, for the reasons explained above.
I can confidently take 'em in the wild knowing I'll be able to address any edge problem with minimal equipment.

Back to this very knife, the steel has Cr7C3 carbides in the Annealed state and I'm pretty confident it will have them to some extent even in its current state, so its corrosion resistance would be ....well :thumbdn::thumbdn:

One more reason to me to steer away from current Spyderco line.


Dan
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Well it's a laminate so I am not all that sure what they had to do HT wise so they didn't blow out the grain in the outer layers.

My opinion just to be fair.
 
Ankerson said:
I don't think it was anything near 65 HRC, my SIC stones ate it like butter, even when making the bevels the same on both sides of blade.

I didn't use anything lower than 320 grit.

I can guess what it I think it was, but I won't. ;)
Click to expand...

Thanks for the information Jim.
 
Forgive me if this has been addressed . . .
I am wondering how real Damascus blades would fare in the test.
By real I mean not a solid core of edge steel with decorative damascus style plates laminated on both sides.
While I am at it I wonder whether lots of layers on the order of 100 plus makes a significant difference in rope cutting performance over say 40 layers.

and some one is going to say depends on the steel so lets say Japanese high carbon like white paper #1.
 
By real I mean not a solid core of edge steel with decorative damascus style plates laminated on both sides.
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So what I am asking about is pattern welded if you'd rather.

For a while I thought the big deal about Damascus was that the layers kept brittle hard steel from breaking during extreme use when made into a battle sword etc.
Then
I read about the carbides all lined up like teeth or some such. So in that case maybe it makes a cutting difference. Heck I don't know. Just asking.
 
You seem to be talking about 2 different kinds of "Damascus". One more s pattern welded, the other is made from wootz ingots, forged at proper temperature. I haven't seen any evidence that one makes a superior blade vs. a well made modern/monosteel blade.
 
me2 said:
You seem to be talking about 2 different kinds of "Damascus". One more s pattern welded, the other is made from wootz ingots, forged at proper temperature. I haven't seen any evidence that one makes a superior blade vs. a well made modern/monosteel blade.
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+1
The first additional problem of damascus being that the two steels must have the same HTing tresholds, to give the very best of each.
The second one being that they should deliver the same austenitic grain size, or you'll eventually experience unexpected chipping.
The only example of properly addressing these prerequisites coming from Sweden ;)

Frankly, a modern monosteel PM blade is more than enough already.
 
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