Bark river's knife steel chart

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knife chop

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Feb 11, 2014
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Can anyone educate me why 3 different steels at 58-60HRC A2, CPM D2 and CPM 154 has the same toughness?
 
knife chop said:
Can anyone educate me why 3 different steels at 58-60HRC A2, CPM D2 and CPM 154 has the same toughness?
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It's not exactly an easy question to answer; there are a LOT of factors involved. Not least of which the fact that charts like these present a very basic overview at best, and can't really be counted on for detail or clarity.
 
james terrio said:
It's not exactly an easy question to answer; there are a LOT of factors involved. Not least of which the fact that charts like these present a very basic overview at best, and can't really be counted on for detail or clarity.
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Mike Stewart and I had a brief conversation regarding the graph. he stated that all steels were at 58-60HRC and its their proprietary HT that makes D2 and CPM 154 as tough as A2.
 
Mike Stewart and I had a brief conversation regarding the graph. he stated that all steels were at 58-60HRC and its their proprietary HT that makes D2 and CPM 154 as tough as A2
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So, did you believe him? :)
 
knife chop said:
Mike Stewart and I had a brief conversation regarding the graph. he stated that all steels were at 58-60HRC and its their proprietary HT that makes D2 and CPM 154 as tough as A2.
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I may be wrong here but I have yet to ever see D2 no matter how well it was heat treated equal A2 in toughness unless a salesman was selling D2.
 
D2 is over-rated. Its edge retention and edge quality aren't that great compared to the thousand years it takes to sharpen it.
 
Hm, I know CPM-3V is the hot stuff nowadays for fixed blades and tough folders, but CPM-4V seems like a really nice option. Same wear resistance as S35VN but twice the toughness.
 
Wolf_1989 said:
D2 is over-rated. Its edge retention and edge quality aren't that great compared to the thousand years it takes to sharpen it.
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Hmm, I disagree. Edge retention of D2 @ 60.5 is much better in my own experience than S30V at the same hardness. Sharpening is a nonissue with the proper equipment. The toughness question though, I don't know if high toughness in D2 would mean good edge holding as well.
 
RevDevil said:
Hmm, I disagree. Edge retention of D2 @ 60.5 is much better in my own experience than S30V at the same hardness. Sharpening is a nonissue with the proper equipment. The toughness question though, I don't know if high toughness in D2 would mean good edge holding as well.
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JMO:

- D2 edge retention is good but not that good. It doesn't impress me enough justify spending more money it.

- I'm not going to buy specialized equipment just for one type of steel, which I don't like anyway.

- I also don't like the feel of D2. I can't put my finger on it. Something just feels chintzy about it; like I wouldn't want to put it through hard use.

I've given it a chance. I've bought two knives in D2. Sold both of them.
 
james terrio said:
It's not exactly an easy question to answer; there are a LOT of factors involved. Not least of which the fact that charts like these present a very basic overview at best, and can't really be counted on for detail or clarity.
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Oh for the luvva...another chart like this? I should make my own and just throw darts blindfolded at names on the wall for the rankings. At least know what Sintered means and how to spell it.
 
knife chop said:
Mike Stewart and I had a brief conversation regarding the graph. he stated that all steels were at 58-60HRC and its their proprietary HT that makes D2 and CPM 154 as tough as A2.
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Bark River does not make knives using D2. :eek:

They have begun using CPM-D2 in a few new prototypes.

Even the chart posted shows CPM-D2. :foot:


Mike Stewart has stated that he was impressed by both the toughness and the edge retention on this PM version of D2.

He also finds the CPM-D2 much easier to grind and sharpen.



Big Mike
 
The Mastiff said:
So, did you believe him? :)
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Ofcourse! LOL

Big Mike said:
Bark River does not make knives using D2. :eek:

They have begun using CPM-D2 in a few new prototypes.

Even the chart posted shows CPM-D2. :foot:


Mike Stewart has stated that he was impressed by both the toughness and the edge retention on this PM version of D2.

He also finds the CPM-D2 much easier to grind and sharpen.



Big Mike
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CPM 154,154CM,ATS 34 / 1095 Cro-van, Regular 1095 / CPM D2, D2.... steels manufactured differently, how much difference is it really? finer grained? toughness? edge retention? :yawn:

To clarify things, when I wrote D2 in my comments I meant CPM D2.:thumbup:
 
The chart is meaningless and thus not really worth the effort to discuss.

There are no units for the y-axis,
The terms "toughness" and "wear resistance" are undefined (e.g. what tests were used to measure them)
Both parameters are plotted together as opposed to a wear resistance scale on the left and a toughness scale on the right.

The chart is total marketting fluff...but then, it's Bark River. :)
 
Big Mike hit the reason the D2 is so tough--it is not D2, but CPM-D2. The powdered steel makes the carbides evenly spaced and sized and increases the toughness.
 
knife chop said:
So do you find bark rivers chart accurate or misleading?
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What I like about the Bark River chart is that it reflects the knife makers opinion about how the steels perform with the HT regime and hardness they use in their knives.

It's goal is to give Bark River buyers a way to compare the steels as used by Bark River.



Big Mike
 
Big Mike said:
What I like about the Bark River chart is that it reflects the knife makers opinion about how the steels perform with the HT regime and hardness they use in their knives.

It's goal is to give Bark River buyers a way to compare the steels as used by Bark River.




Big Mike
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Fair enough.

Their A2 must have the same low toughness of a PM 154 and D2 then. I say that because I saw the destruction test of the bravo 1. It might not be scientific but that A2 proved to be on the brittle side compared to other A2. Just my conclusion.
 
knife chop said:
Fair enough.

Their A2 must have the same low toughness of a PM 154 and D2 then. I say that because I saw the destruction test of the bravo 1. It might not be scientific but that A2 proved to be on the brittle side compared to other A2. Just my conclusion.
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It's not one of those ridiculous "Knife A is a piece of junk because it broke when I hit it with a sledgehammer while trying to baton through concrete" loltests is it?

I've used, and at times abused, my Bark River knives in A2, 3v, and S35VN and have never felt any hint of "brittle". I had the cutting edge of an A2 knife get damaged once, but I expected it because I was absolutely abusing the knife.

I'm not sure of the need for super steels, other than that you can make the same style of knife with a thinner blade that can handle the same amount of abuse.
 
knife chop said:
Their A2 must have the same low toughness of a PM 154 and D2 then.

I say that because I saw the destruction test of the bravo 1.

It might not be scientific but that A2 proved to be on the brittle side compared to other A2.

Just my conclusion.
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I have personally tested many BR knives in A2 steel, often big blades that I used to chop, pry and baton with.

Being they where test blades with a lifetime warranty, I did things I wound not normally do with my knives.

I've chipped and rolled some edges, and have knocked a few scales loose, but I can't say I've encounter this "Low Toughness" that you have concluded to be an issue.


Maybe if you went out and put some BR A2 knives to actual field use you might come up with a different conclusion.


But I'm sure that destruction test was very entertaining.



Big Mike
 
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