Call for Charpy toughness samples

rodriguez7 said:
I’ve made a few big and small blades from this steel. Bought from chuck. Still trying to find time to dial in the heat treat. But what I’ve made so far has held up to whatever I could throw at it! It is very tough, but I don’t think it’ll beat ztuff.
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Can’t wait for the tests to proof your impressions! A Ztuff coupon heat treated to max toughness (will probably have a lower hrc reading than 61) should be even higher on toughness than the ones Larrin tested so far!

So: Ultrafort, S7, NZ3 (~S1), 1v, Ztuff (tempered to achieve max toughness) and A8mod are the top contenders to steal the 8670 crown.:)
 
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hugofeynman said:
Can’t wait for the tests to proof your impressions! A Ztuff coupon heat treated to max toughness (will probably have a lower hrc reading than 61) should be even higher on toughness than the ones Larrin tested so far!

So: Ultrafort, S7, NZ3 (~S1), 1v, Ztuff (tempered to achieve max toughness) and A8mod are the top contenders to steal the 8670 crown.:)
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I really think 6150 can be on top too. I have done bad things to my ztuff knife this days and it has not taken less dmg than 6150. (BTW keep your knives away from construction nails and screws... )
Giedy also told me that his 6150 is a bit tougher than nz3.
I will ask him if he can send a sample.
I'm working with him with 2 new blades, let's see what he says.
 
Salival said:
I really think 6150 can be on top too. I have done bad things to my ztuff knife this days and it has not taken less dmg than 6150. (BTW keep your knives away from construction nails and screws... )
Giedy also told me that his 6150 is a bit tougher than nz3.
I will ask him if he can send a sample.
I'm working with him with 2 new blades, let's see what he says.
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Please convince him to do so! I already gave Warren and Larrin a piece of NZ3 from another Polish maker (LKW Knives, a gentleman to deal with), now we need 6150 also! And if it’s even tougher than NZ3 (he’s right, less carbon should make 6150 tougher than NZ3 and 5160), let’s bring it to the test!:D
If he doesn’t have the time to make the coupons, ask him if he can donate a piece of steel big enough to, at least, three coupons (cut parallel to the rolling direction of the steel).
 
So it sure lookalike the old theory that says that 52100 and AEB-L are pretty similar in use seems to be accuarate.
 
jdm61 said:
So it sure lookalike the old theory that says that 52100 and AEB-L are pretty similar in use seems to be accuarate.
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Wait until we see 15n20. I’ve said for years it’s like non stainless aeb-l. 8670 is better than I expected too.
 
Willie71 said:
If you have a protocol you want tested, pm it to me, and I’ll follow it.
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According to Crucibles data sheet (or my interpretation of those values:p), a good starting point would be: 1725F 30 min soak and 400F temper (two hours(???), two tempers(????)). That should put this steel right in his toughness peak and with an interesting hardness value (57). Because we are reaching max toughness, I would avoid cryo. I’m sure RA% with this steel would not be a problem, this thing is designed to use low temper protocols, not “forced” to be low tempered, as we like to do nowadays to some pm steels.;)
 
Salival said:
I really think 6150 can be on top too. I have done bad things to my ztuff knife this days and it has not taken less dmg than 6150. (BTW keep your knives away from construction nails and screws... )
Giedy also told me that his 6150 is a bit tougher than nz3.
I will ask him if he can send a sample.
I'm working with him with 2 new blades, let's see what he says.
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Have you bought your Ztuff knife overseas? Who was the maker? Not usual to see that steel used in Europe.
 
The two issues that I see with the 8670 is lack of larger stock and the idea that you don't seem to be able to run up the hard
Willie71 said:
Wait until we see 15n20. I’ve said for years it’s like non stainless aeb-l. 8670 is better than I expected too.
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ness like you can with 52100, AEB-L, CFV and from what I have heard, 15N20. L6 typically has that second "hump" at 61Rc wherein is like 85% or so as tough as it is at 57Rc. I an wondering of the L6 that was test was in that "dip" between those two peaks.
 
That's weird because it is made by Zapp in Germany. It may be just not be commonly used for knives anywhere yet.
hugofeynman said:
Have you bought your Ztuff knife overseas? Who was the maker? Not usual to see that steel used in Europe.
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jdm61 said:
The two issues that I see with the 8670 is lack of larger stock and the idea that you don't seem to be able to run up the hard

ness like you can with 52100, AEB-L, CFV and from what I have heard, 15N20. L6 typically has that second "hump" at 61Rc wherein is like 85% or so as tough as it is at 57Rc. I an wondering of the L6 that was test was in that "dip" between those two peaks.
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I’ve made a few kitchen knives in 8670 at Rc63, and they perform quite like 15n20.

I’ll check the L6 samples, and see if I did higher hardness samples. I have one piece left here, and can push the hardness up.
 
I was just going by the drop off that we saw in the testing of the 8670. Maybe higher AND lower for the L6.. The max hardness on the charts is like 57-58, shined towards 57 and then that second hump is at like 61, BUT there is an actually dip on the chart between like 58 and 60.
Willie71 said:
I’ve made a few kitchen knives in 8670 at Rc63, and they perform quite like 15n20.

I’ll check the L6 samples, and see if I did higher hardness samples. I have one piece left here, and can push the hardness up.
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jdm61 said:
The two issues that I see with the 8670 is lack of larger stock and the idea that you don't seem to be able to run up the hardness like you can with 52100, AEB-L, CFV and from what I have heard, 15N20.
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What thicknesses are you looking for? We have .084", .102", .126", .138" .170", .186", .210" & .224" in stock. We have a chef knife that is HRC 62 that hammered through steel tubing with no damage to the edge.
jdm61 said:
That's weird because it is made by Zapp in Germany. It may be just not be commonly used for knives anywhere yet.
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Z-Tuff was designed by the same metallurgist who invented CPM 3V. He works for Zapp here in the US. The powdered billet was made by Carpenter for Zapp so it was made with the super fine powdered metal. It is designed and made here in the US. We just received our shipment of .098 Z-Tuff.

Chuck
 
Ah. I did not know that about the manufacturing of Z Tuff although I had heard that the metallurgist who gave us 3V also gave us this cool stuff. As for the 8670, this is first that I have seen of stock thicker than like .1875. Good work once again!!!!!!! Still a little thin for tactical tomahawks perhaps. ;) I may have to score some of tha .098 for something like a thin Kephart. Who has the recipe for the HT? From what I saw, Zapp seems to suggest a fairly complex process so I am not inclined to try it in my Paragon.
Alpha Knife Supply said:
What thicknesses are you looking for? We have .084", .102", .126", .138" .170", .186", .210" & .224" in stock. We have a chef knife that is HRC 62 that hammered through steel tubing with no damage to the edge.
Z-Tuff was designed by the same metallurgist who invented CPM 3V. He works for Zapp here in the US. The powdered billet was made by Carpenter for Zapp so it was made with the super fine powdered metal. It is designed and made here in the US. We just received our shipment of .098 Z-Tuff.

Chuck
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jdm61 said:
Ah. I did not know that about the manufacturing of Z Tuff although I had heard that the metallurgist who gave us 3V also gave us this cool stuff. As for the 8670, this is first that I have seen of stock thicker than like .1875. Good work once again!!!!!!! Still a little thin for tactical tomahawks perhaps. ;) I may have to score some of tha .098 for something like a thin Kephart. Who has the recipe for the HT? From what I saw, Zapp seems to suggest a fairly complex process so I am not inclined to try it in my Paragon.
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1900fx45min, plate quench, cryo, 400 temper x2. Gives you Rc60. 1950 30 min, cryo, 400fx2 gives you Rc61/62. Rc62 seems to be where it tops out. It’s more sensitive to tempering temps than other similar steels. The tested sample was 1925f, cryo, 300f temper for Rc61.5.
 
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jdm61 said:
That's weird because it is made by Zapp in Germany. It may be just not be commonly used for knives anywhere yet.
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Only now I’ve realized that Zapp is a German company! I thought it was based in US!

Although Ztuff is from Germany, never heard about European makers using that steel.
 
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