Charpy results for ZDP-189

HoB said:
I don't know. This seems to me like comparing apples and oranges. Edgeholding is both a function of abrasion resistance and hardness. Even if S90V is as abrasion resistant as ZDP-189 but not as hard, its edgeholding will be much inferior for many applications. I don't know what happens to S90V when you run it at Rc67, maybe it becomes like glass and unusable as a blade steel. In that case you really can not compare S90V and ZDP-189 at very high hardnesses. I don't think the claim was made that ZDP-189 could be hardened without any loss in toughness. I read it more as being still of useful toughness at rediculus hardnesses. I doubed that ZDP-189 will ever become a factor in large fixed blades or any other application where toughness becomes more important than edge retention.
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Which applications? Wayne Goddard's rope cutting tests show that the vanadium-added steels cut as long as a hard steel without, and the CATRA test shows the same thing. Would slicing tomatoes (or something else) give a different result? S90V can't be hardened to 67 Rockwell, only ZDP-189 can, even carbon steels can only make it up to 67-68 right after quenching, and then they are lower after tempering.
 
For the types of knives that I use, I can't say that ZDP does anything for me. I want something that is pretty tough so S30V appeals to me more than the super hard but not very tough steels. I don't recall how S30V stands up against non-stainless steels, but it is supposed to be even tougher and more corrosion resistant than 440C.
 
YSS steels
Does anybody handle this YRX7 steel?

YSS.gif


Thanks, Vassili.
 
I don't know of anyone who use the YRX7, but if it gives it a C for corrosion resistance, than it might actually be a carbon steel, people complain about the stainless steels rusting too fast, so if it gets a C compared to those other steels, than it has very poor corrosion resistance. The ZDP247 looks good according to that chart though. I wish they knew the exact composition. Comparing to other steels on the chart, S30V should get at least A's on all three categories, maybe even an A+ or two.
 
Larrin said:
Which applications? Wayne Goddard's rope cutting tests show that the vanadium-added steels cut as long as a hard steel without.
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I don't quite follow, how does that apply here. As far as I know, nobody knows the exact composition of ZDP-189. So you don't even know whether it contains Va or not?

As far as I know CATRA tests are tests specifically for wear resistance. Often in normal use (like cutting Tomatos on a cutting board or wittling hard wood), the edge rolls rather than that it is being worn. The harder the blade the less roll you have and the longer the edge retention. In applications for which INFI was engineered the edge degrades mostly through micro chipping for which neither outstanding wear resistance nor hardness will improve edge holding. Obviously, ZDP-189 would be misplaced in such an application. On the other hand, as far as I know S90V is not overly tough in comparison with A2 or 52100 either.

For a pocket knife that is intended as slicer, and not as no-bars-hold SD knife, I am very excited about ZDP-189 and can't wait to try one out.
 
Nobody question CPM S30V as being current supersteel on the market. But it will be really interesting to know what exactly this two steels are - ZDP 189 and YXR7. Both looks very promising.

Thanks, Vassili.
 
HoB said:
I don't quite follow, how does that apply here. As far as I know, nobody knows the exact composition of ZDP-189. So you don't even know whether it contains Va or not?

As far as I know CATRA tests are tests specifically for wear resistance. Often in normal use (like cutting Tomatos on a cutting board or wittling hard wood), the edge rolls rather than that it is being worn. The harder the blade the less roll you have and the longer the edge retention. In applications for which INFI was engineered the edge degrades mostly through micro chipping for which neither outstanding wear resistance nor hardness will improve edge holding. Obviously, ZDP-189 would be misplaced in such an application. On the other hand, as far as I know S90V is not overly tough in comparison with A2 or 52100 either.

For a pocket knife that is intended as slicer, and not as no-bars-hold SD knife, I am very excited about ZDP-189 and can't wait to try one out.
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The Japanese usually use Tungsten, and the YSS chart affirms this, though I forgot about the hard carbides that are also in ZDP-189. I never said S90V was tough in comparison to A2 or 52100, but it does have comparable toughness to other major stainless steels. My point is that ZDP has pathetic toughness even compared to other stainless steels. I don't think the few knife companies using it should have it to near the hardness they are bringing it to.
 
I guess all I want to say is that personally I want to wait till I have tried those steels out and have something to compare to, before I declare a steel as not tough enough or as "better" or "worse" overall.
 
I've been wondering about the cowry as well. I had only seen them on seki cut, but now Ken Onion's Hawaii is utilizing it also.
Me need specs.
 
Um, so where is the Japanese division of Bladeforums? All these are quite interesting, but it seems we are faced with a lack of data and experience with them. Maybe the steel freaks over there just don't have the time, or aren't into Western knives enough to bother learning English or lack the interest to come here? Steel is one of Japan's major industries and some of the plants even employ master swordsmiths so they can study their blades in the laboratory and incorporate some of their properties into industrial steels. So the practical information is probably out there somewhere.... Wish I could recognize more than a handfull of kanji, but they didn't teach Nihongo when I went to school and I don't seem to be picking up much by osmosis :grumpy:

Not to be a whining bottom-feeder, but the next question is: when are these "alphabet-soup" steels going to become common and cheap enough for us to play with them? I mean, even though I love the knife, I was hard pressed to justify buying one of Watanabe's Kintaro-Ame blades, let alone try to cough up over $600 for something in ZDP or Cowry, just to compare it to S30V, M2 or 52100 etc.
 
I doubt ZDP will ever become common. The Japanese like to keep their steels in Japan.
 
Let me correct you a little bit - ATS34, VG-10, AUS6, AUS8... all are Japanese steels.

As well as half or even more of Spyderco made in Japan, Fallkniven - entierly in Japan, AlMar, SOG, some KaBars etc...

Thanks, Vassili.
 
ATS-34 has made it in to America, but all of the knives I know of with VG-10 are made in Japan. There are many other Japanese steels that have not made it in to America. Trust me, the Japanese like to keep their steels. If you get lucky it will make it in to America, but since it looks like a low-production steel, I doubt it. Since ATS-34 was planned as a big-time steel, it is now sold in the U.S., I suspect VG-10 will be available in America too, if it isn't already. Those other companies you mentioned are making the knives in Japan, which is why they can get the steel, because they are in Japan. This means that it won't likely get to be a big time steel, especially since it is so expensive. Technically they could start making the knives in large amounts and selling them in America, but I doubt it.
 
Spyderco making knives in US out of VG-10. I think it is more about moving into already tight market, more about acceptance etc. not because Japanese don't like to sell teir products everywhere. There is no Japanese makers directly present here and they did not developed Internet the way we can easyly buy directly from Japan. I know only this site in Europe which selling Japanese knives, blades even steel (only Shirogami and Aogami).
http://www.dick.biz
And only one site offering Hattory
http://www.worldknives.com/

Thanks, Vassili.
 
YXR 7:
0.8 Carbon
5.0 Chromium
5.0 Molybdenum
1.1 Tungsten
1.1 Vanadium

It is conventionally melted and is a watered down high speed steel. It is used in tooling applications like forging where high hardness and heat resistance is required.
 
M2 is almost the same with more Tungsten and Vanadium:

C=0.95-1.05
Cr=3.75-4.5
Mo=4.75-6.5
W=5-6.75
V=2.25-2.75

Mn=0.15-0.4
Ni=0.3
Si=0.2-0.45

Thanks, Vassili.

I wish Benchmade will make one of HS model with thicker blade and harden it to 64HRC (right hardeness for MS as I understand) with BC coating, and wide blade ... I am almost crying ...
 
I am right now wondering whether Fallkniven's " Super Gold Powder Steel" used on their U2 folder is the ZDP-189. The steel is also heat treated to 62-64 HRC.
 
lreed said:
I am right now wondering whether Fallkniven's " Super Gold Powder Steel" used on their U2 folder is the ZDP-189. The steel is also heat treated to 62-64 HRC.
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The composition is posted on Fallkniven's website, it's close to Uddeholm's ELMAX, or Crucible's S30V.
 
Data I have

SGPS C=1.4 Cr=15 Mo=2.8 V=2.0 Mn=0.4 S=0.03 P=0.03 Si=0.5
Elmax C=1.7 Cr=17 Mo=1 V=3 Mn=0.3 Si=0.4
S30V C=1.45 Cr=14 Mo=2 V=4 N=0.2

Thanks, Vassili.
 
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