I have a moral/ethical question on forging.

Kevin R. Cashen said:
Well, it would probably be much more accurate to say that I could rival a research company's lab from about 30 years ago. I
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That is still cool, my anvil is more than 100 years old but it still does the job just like a new one. I am a science nerd from way back so I get it.
 
Kevin R. Cashen said:
Well, it would probably be much more accurate to say that I could rival a research company's lab from about 30 years ago. I am just a bladesmith and am no where near wealthy enough to afford any of the equipment that you would find in a modern lab. So I have gotten good at finding, and refurbishing, old equipment that those labs are done with. It really has no practical application in bladesmithing, but it is really handy in my side hobby/obsession of ferrous metallurgy.



The safest part of that question to answer is the surest- it is all about the heat, and those extra cycles, when done right, can make some definite changes. Now on the hammer side of the equation I must be much more cautious, interesting things can happen but it would be irresponsible to make any sort deeper connections, when it is still all about the heat, even when the hammer is doing things; beating on steel without heat only induces needless strain, both in you and the steel.
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So a stock removal guy would benefit from multiple normalizations of a given blade? ( mimicking the in and out of the forge) How many cycles would be advantageous? Would it vary depending on steel type? I am working with A-2 currently...if this is something that will give me a better blade...I'm all for it.
 
Only if there are conditions that can be improved by it. Heavy carbide segregations is one case where the answer would be yes, but just one or two good normalizations should do the trick. This is the case where heavily spheroidized steel has a hard time reaching full hardness but after one good normalizing the problem goes away.
 
Kevin R. Cashen said:
Only if there are conditions that can be improved by it. Heavy carbide segregations is one case where the answer would be yes, but just one or two good normalizations should do the trick. This is the case where heavily spheroidized steel has a hard time reaching full hardness but after one good normalizing the problem goes away.
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Thank you Kevin! Good to know.
 
Kevin R. Cashen said:
Only if there are conditions that can be improved by it. Heavy carbide segregations is one case where the answer would be yes, but just one or two good normalizations should do the trick. This is the case where heavily spheroidized steel has a hard time reaching full hardness but after one good normalizing the problem goes away.
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Even high primary carbide volume steels? like n690 / 440c etc?
 
Well, we need to remember that in a stainless alloy normalizing, i.e. heat to full solution and air cooling, is no longer normalizing, as it is technically hardening. And not a very good hardening at that, as full solution is usually not a good idea for hardening if it will result in hypereutectoid levels.
 
Kevin R. Cashen said:
Well, we need to remember that in a stainless alloy normalizing, i.e. heat to full solution and air cooling, is no longer normalizing, as it is technically hardening. And not a very good hardening at that, as full solution is usually not a good idea for hardening if it will result in hypereutectoid levels.
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Can it in some way be used to disperse and reduce the size of the carbides? Like if you harden from that temp fully and then harden from a lower temp to reduce grain size... and get the right amount of carbon in solution... I mean if this pic below is the carbides in n690 and D2 then ithere must be some what to make it better... this after a few short FeCl applications....
 

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Ah yes, I see what you mean that is some nasty alloy banding. Under the microscope you would see those lines as being large collections of primary spheroidal carbides. For this you could try a high hardening heat, immediately followed by a more reasonable one (cooling in between, of course). One could also play with isothermal spheroidal anneals that rely on DET, but you would then have fewer, but much larger spheroids, that would be selfish with their carbon.
 
Kevin R. Cashen said:
Ah yes, I see what you mean that is some nasty alloy banding. Under the microscope you would see those lines as being large collections of primary spheroidal carbides. For this you could try a high hardening heat, immediately followed by a more reasonable one (cooling in between, of course). One could also play with isothermal spheroidal anneals that rely on DET, but you would then have fewer, but much larger spheroids, that would be selfish with their carbon.
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Whaddaya mean my Stainless NieuWootz is nasty??!! ;-) :D
OK, so essentially I quench from 1080- 1100C - (1080C usually stipulated as the max aus temp) would tempering high to set up small tempering carbides be useful? and then use 1040 - 1050C and quench and LN and temper? I suppose don't quench fast enough to crack would be useful, a plate quench should be fine... would it be useful to extend the quench to make most martensite possible? I suppose RA would be of no issue during this phase...

I usually use 1060 (hunters)-1080 C(Kitchenknives) oil quench Liquid nitrogen and temper 150C, liquid nitrogen and temper 180C.
 
https://www.researchgate.net/profile/David_Bombac/publication/257713217_Study_of_Carbide_Evolution_During_Thermo-Mechanical_Processing_of_AISI_D2_Tool_Steel/links/0c960525dcc7db5306000000/Study-of-Carbide-Evolution-During-Thermo-Mechanical-Processing-of-AISI-D2-Tool-Steel.pdf?origin=publication_detail

I might be reading it wrong... but it seems 1160C and no forging might be good for D2 type steels... but i struggle to make sense of it all as there are a lot of things in there that i dont quite get...
 
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