Call for Charpy toughness samples

I think I’ve convinced some friends to make and heat treat pieces in K600 (0,45% carbon, 4% nickel), A8mod and Ultrafort (Maraging steel). Will probably take some time until they finish it.
Very curious about the 4% nickel and a8! Should be some tough stuff. If the a8 is heat treated similar to infi, it’ll be very interesting! Can’t wait to see. Larrin has his work cut out for him!!
 
I'd love to have a forged piece of the titanium alloy I use for swords tested. Someone else would have to be able to surface grind the sample to final tolerances, though. What a tiny test sample! I might torch it in the HT. :D Is it not a V-notch test?
 
We tested the three 15N20 samples and got somewhat disappointing results. We got values of 8.9, 9.0, and 23.8 ft-lbs. So we got two low values and one much higher value, meaning it is difficult to conclude much from the tests. None of those values are anywhere close to the toughness measured for AEB-L. The results might be inconsistent due to their prior use as saw blades, but we're not really sure.

The heat treatment was: subcritical anneal at 1175°F, austenitize at 1475°F, quench in Parks #50, liquid nitrogen for 20 minutes, temper 2x at 375°F for final hardness of 60 Rc.
 
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We tested the three 15N20 samples and got somewhat disappointing results. We got values of 8.9, 9.0, and 23.8 ft-lbs. So we got two low values and one much higher value, meaning it is difficult to conclude much from the tests. None of those values are anywhere close to the toughness measured for AEB-L. The results might be inconsistent due to their prior use as saw blades, but we're not really sure.

The heat treatment was: subcritical anneal at 1175°F, austenitize at 1475°F, quench in Parks #50, liquid nitrogen for 20 minutes, temper 2x at 375°F for final hardness of 60 Rc.
I’ve been testing some 15n20 pieces myself, and have not got the toughness I’ve heard so much about, these are impact and cut tests, including hammering through various mediums. Nowhere near what your doing! But in my testing, 8670 is holding up much better! Curious as to why they tested so low, considering the nickel content! It’s still an awesome steel, but not what I thought it was. I’m getting better edge retention, impact and lateral toughness out of 8670! I’m anxious to see how that tests out. Plus it’s cheaper.
 
For knife steels, v-notch testing results in extremely low values.

Isn't that just because they're hardened so much? I thought most steel types could be tempered to be tougher but softer.
 
Is that just because they're hardened so much? I thought most steel types could be tempered to be tougher but softer.
One major reason is the high hardness, and they can indeed be tougher with lower hardness, generally. Another major reason is the presence of carbides.
 
One major reason is the high hardness, and they can indeed be tougher with lower hardness, generally. Another major reason is the presence of carbides.

Ahhh the carbides. Makes sense - in titanium, just there mere presence of some alloying elements even at very low levels can make the alloy significantly more brittle or less tough, at any "hardness."
 
Cool info, I was only aware of the V-notch test, with large test samples. Larrin it would be cool to see some pics of the testing. :]
 
Has 5160 already been done? How about the simple steels like 1075/1095 for comparison purposes? L6 and 9260 would also be interesting if available.

Testing these is interesting if for no other reason than those are considered sword steels and thus are supposed to be extra tough.
 
Has 5160 already been done? How about the simple steels like 1075/1095 for comparison purposes? L6 and 9260 would also be interesting if available.

Testing these is interesting if for no other reason than those are considered sword steels and thus are supposed to be extra tough.

I’m doing W2, and if I have a piece of 1095 left, I’ll do a sample of that too.
 
You mean other than on bladeforums?

Yes, in a professional journal as examples of what can be done in “real world conditions” rather than with ideal equipment. It might be interesting to float this idea.

Warren
 
Would love to see some 1075 and 1084 compared to the tool steels and pm stuff as well. I have nothing to contribute but happy to donate to buy more steel
 
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