Toughness testing of AEB-L, Niolox, CPM-154, 19C27, 40CP, and D2

DevinT said:
On a Charpy testing machine with 1/4 size test samples, a common size. (2.5 mm x 10 mm x 55 mm). Heat treated then ground to size, (+/-.001)tested in the longitudinal direction. 3 samples per alloy, results averaged. Hoss
Click to expand...
were the samples un-notched or notched? just trying to see how other steels fit in with the data. Crucible says their O1 at Rc61-63 has a C-notch rating of 30 ft-lbs, which would fit the data you show.
 
scott.livesey said:
were the samples un-notched or notched? just trying to see how other steels fit in with the data. Crucible says their O1 at Rc61-63 has a C-notch rating of 30 ft-lbs, which would fit the data you show.
Click to expand...
They are unnotched. The values should not be compared to Crucible which are full size charpy c-notch.
 
I was fortunate enough to be turned on to AEB-L not long after I started making knives in 2007. My old mentor, Johnny Warner bought several sheets of the 1/8" stuff back in the 80's and gave me a sheet to play with. Ol' Hoss was kind enough to share his H/T knowledge with me and I've never looked back.
Funny thing is that I bought some of the thicker stuff when it became available but I still use 1/8" or less most of the time with 3/32" being what I use the most.
 
Lapedog said:
If cpm154 is as tough as 154cm (Potentially even tougher due to smaller carbides) then I imagine it would be even tougher than s35vn. Apparently 154cm and even 440c are quite tough for stainless.
Click to expand...

I thought 154CM and CPM154 were the same steel???
 
Larrin Would you be Interested in testing some 15n20. I can do the heat treat and cut to what ever size you want and ship to you. I dont know what thickness you would need but the thickest I have is .090 but I could forge weld some togather to get the thickness you needed.
 
JTknives said:
Larrin Would you be Interested in testing some 15n20. I can do the heat treat and cut to what ever size you want and ship to you. I dont know what thickness you would need but the thickest I have is .090 but I could forge weld some togather to get the thickness you needed.
Click to expand...
Sure, if you could add in a small handful of other steels of interest; what do you have? We need at least 3 per steel and heat treatment for a good average. They need to be 2.5 x 10 x 55 mm with the long dimension in the rolling direction. They need to be ground on all 4 main surfaces and parallel. If you have a small surface grinder then that would probably be sufficient.
 
I’m really interested to see how 15n20 tests!! I would like to see 8670, and w2 sometime! I’m really liking these 3 steels!
 
Larrin said:
Sure, if you could add in a small handful of other steels of interest; what do you have? We need at least 3 per steel and heat treatment for a good average. They need to be 2.5 x 10 x 55 mm with the long dimension in the rolling direction. They need to be ground on all 4 main surfaces and parallel. If you have a small surface grinder then that would probably be sufficient.
Click to expand...

Would you like some z-wear in cryo plus low temper, and no cryo plus high temper to compare? I dont have a surface grinder but I’m sure I can find someone who does.
 
Willie71 said:
Would you like some z-wear in cryo plus low temper, and no cryo plus high temper to compare? I dont have a surface grinder but I’m sure I can find someone who does.
Click to expand...
You should also add in a condition with both cryo and a high temper. And try to temper them to approximately the same hardness. Good luck finding your surface grinder guy!
 
Larrin said:
You should also add in a condition with both cryo and a high temper. And try to temper them to approximately the same hardness. Good luck finding your surface grinder guy!
Click to expand...

Cryo with high temper before first temper, or after first temper? I should be able to get the hardnesses close based on my previous testing. I’m getting 1.5-2 Rc points higher than the datasheets using cryo plus low temper at the temps they list.

I’ll see what stock I have left, and order in the right stuff if I need to.
 
Willie71 said:
Cryo with high temper before first temper, or after first temper? I should be able to get the hardnesses close based on my previous testing. I’m getting 1.5-2 Rc points higher than the datasheets using cryo plus low temper at the temps they list.

I’ll see what stock I have left, and order in the right stuff if I need to.
Click to expand...
Cryo after quenching, before any tempering.
 
I’m loving this! Very interesting. You guys are really schooling me! I’m learning a lot
 
Willie, I have some z wear heat treated by peters, and it’s very impressive stuff. Is dry ice sufficient for this, or do you really need cryo for best results? My oven will be in in a month, but I still don’t have a deware. But I have access to dry ice! Thanks
 
rodriguez7 said:
Willie, I have some z wear heat treated by peters, and it’s very impressive stuff. Is dry ice sufficient for this, or do you really need cryo for best results? My oven will be in in a month, but I still don’t have a deware. But I have access to dry ice! Thanks
Click to expand...

It needs full cryo to get full hardness. I tried dry ice and didn’t get the full bump. Many of my results are listed here:

https://www.bladeforums.com/threads/zapp-z-wear-experience-and-heat-treat.1439207/

I agree that z-wear is impressive when heat treated according to the datasheet. With cryo and low temper, the fine edge stability is better than anything I’ve used so far. It’ll blow your mind.

Nathan said M4 and V4E as being the best he’s seen. They have a bit more alloying than z-wear, but they are similar steels. I’m curious how much different than they would be in performance.
 
Last edited:
By the way, that paper I just quoted above uses the same unnotched sub size specimens we used: 2.5 x 10 x 55mm. They give values in J/cm^2 but when converted to J and then ft lbs we used I get approx 6 ft lbs for the cryo versions and 14 ft lbs without cryo. Unfortunately the paper doesn’t list the orientation used so there is a possibility they were transverse which would lower the values. Maybe I can email the author.
 
You must log in or register to reply here.
Back
Top