Heat Treatment - Crystal Weaving Foundation

[Chris "Anagarika"]

Luong,

Try to understand your comment against the picture, the smooth one is cleanly broken because of plate martensite, while the rough looking surface is because the material had higher yield, thus being torn apart after more elastic change taken place, thus the surface became rougher?

 

[Cobalt]

Ammo can (or equivalent) is required for CWF. Plate/P50/etc uses in conjunction with the ammo can. There will be more equipment needed but you can get them locally.

edit to add: mid-night oil ht without recall my earlier statement aust temp for steel with Nitrogen added... 14C28N got 63rc, only tiny bit better than a reference conventional ht 62rc. FAILED. aust too high at 2025F. Brittle edge failed to whittle my usually suite (African Blackwood, bone,..).

Ok, so Luong, the oil is the important step in your weaving process?

If so are you varying the temperature of the oil? Starting off high and slowly bringing it down to a low point, then moving to another media? then back up?

 

[BluntCut MetalWorks]

Chris,

Yes, the weaved part is mostly interlocked lath martensite, so it torn apart. While the smooth part cleaved off surface - intergranular, which indicative of plate mart.

Luong,

Try to understand your comment against the picture, the smooth one is cleanly broken because of plate martensite, while the rough looking surface is because the material had higher yield, thus being torn apart after more elastic change taken place, thus the surface became rougher?

 

[BluntCut MetalWorks]

Sorry, mid-night oil was figurative speak of try to ht in wee hours (mostly to irritate sleeping people close by ) Nevertheless, your complex guess is excellent. If you are the experimenter - what would you do/proceed? I am intrigue by your 'then back up?' - I like to know more of your thought on that.

Ok, so Luong, the oil is the important step in your weaving process?

If so are you varying the temperature of the oil? Starting off high and slowly bringing it down to a low point, then moving to another media? then back up?

 

[Cobalt]

Sorry, mid-night oil was figurative speak of try to ht in wee hours (mostly to irritate sleeping people close by ) Nevertheless, your complex guess is excellent. If you are the experimenter - what would you do/proceed? I am intrigue by your 'then back up?' - I like to know more of your thought on that.

Just a guess that you are using the ammo cans for different temp quench. Your main tank at a certain temp, plate quench, ammo can at a certain temp, them cryo, then ammo can at a certain temp to transition back up. Just a guess. That's all.

 

[BluntCut MetalWorks]

:thumbup: Very good guess. LN2 is part of CWF, I haven't try dry-ice but it would work well enough for many steels.

Earlier, I mentioned there are additional equipment are needed but can buy them locally... Turn the ammo can into a weaver. Also start looking for 5 gals of eyeless unicorn tears - joking!

Just a guess that you are using the ammo cans for different temp quench. Your main tank at a certain temp, plate quench, ammo can at a certain temp, them cryo, then ammo can at a certain temp to transition back up. Just a guess. That's all.

 

[Cobalt]

uggh, this thread is like a cross of the show Ancient Aliens + Lord of the Rings+ how it's made. I am going to go slay some Orcs.

 

[BluntCut MetalWorks]

My plan to shoot 2 videos releasing CWF info got delayed by a nasty cold - lost voice.

Up & about, I shot a 95 seconds no-talk video.

Conventional hardened D2 known to be brittle. At 67rc should be like glass. At below transition temperature, this blade should behave like a thin sugar glass.

CWF ht (hardened) D2 at 67rc LN2 freezed did well with hammer tapped through 16D nail.
[video]https://youtu.be/_L5eLHSwpjY[/video]

Close up on edge afterward

Thermal expansion sounds boring but you will probably hear more about it in CWF disclosure.

Look at CPM154 (a precious nugget of) data on Coeff of Therm Exp). It's not a shocker to see high alloy steels transition temperature way above 0C.
https://www.alphaknifesupply.com/Pictures/Info/Steel/CPM154-DS.pdf

Researchers fancy-up ways to create actual structure to combat thermal expansion: basically to preserve strength, minimize dimension flux and toughness in structural environment.
http://www.seas.harvard.edu/hutchinson/papers/LowCTE-7-07.pdf

CWF conceptual approach is doing the same but within material/matrix itself.

LOL - I was puzzled to received a heavy package. Heheh ammo cans...

 

[Chris "Anagarika"]

Luong,

So the damage is isolated to impacted area without propagating further and shattered the whole frozen blade ... whoa

I'm wondering if Hitachi White said to be the purest carbon steel will be most suitable for CWF? Why do you choose D2 for the test?

 

[BluntCut MetalWorks]

CWF HT is applicable to most Fe+C matrix steels, except has low to zero benefit for low alloy steels with less than 0.2%C. So yes, Hitachi white#1-2 and heck their lower grade #3-5 as well, would get better result with CWF HT.

D2 because it is near worse-case scenario end of brittleness at room & below transition temperature. A sharpened iron bar (or bar made out of gummy bear or rubber) would be brittle when freezed with LN2. Thus far CWF weaved-matrix LN2 frozen blades performed extraordinary well (I haven't able to establish a unbroken baseline/control conventional ht blades yet).

A good read for many of you - http://www.msm.cam.ac.uk/phase-trans/2004/Tempered.Martensite/tempered.martensite.html

From Table 2: Stored energies of a variety of microstructures
you can see how much 'stored energy' in martensite. That's right folk 'a loaded spring'! Now try to compress it (thermal contraction) with LN2 - normal martensite matrix would crumble even by small impact load. But but the D2 blade in video survived

Luong,

So the damage is isolated to impacted area without propagating further and shattered the whole frozen blade ... whoa

I'm wondering if Hitachi White said to be the purest carbon steel will be most suitable for CWF? Why do you choose D2 for the test?

 

[wensynch]

So this would follow the line of cyrogenic treatment kind of like what ZT markets?

 

[BluntCut MetalWorks]

Please rephrase your question. I don't think, zt ht with cryo is related to CWF ht or test frozen blade.

So this would follow the line of cyrogenic treatment kind of like what ZT markets?

 

[wensynch]

I meant a process which included some sort of cycling between heat and deep freeze through some sort of specified intervals. Shrinking the spaces between the grain or steel particles.

So, I guess the cyro treatment without the cyro, or dried ice.

 

[Cobalt]

So this would follow the line of cyrogenic treatment kind of like what ZT markets?

No, it has nothing to do with cryo. He froze the blade and then hammered it into a nail to see if it would propagate a fracture all the way through the blade and it did not. Good test. Problem is that there is no reference. If you take a standard D2 blade and freeze it will it do the same if shaped the same or will it fracture? who knows.

 

[BluntCut MetalWorks]

Cobalt - See red bold... Yeah, I broken plenty of test & some production blades at LN2 temperature. I couldn't find an instance of any samples or reference on the internet which can do this either, therefore Can't Establish Baseline/Ref/Control - unless calling broken pieces as reference.

edit: ok just went and killed my Mora knife froze at LN2 temp against 16D nail. Tap = 2 pieces.
edit2: just rockwell tested of mora blade, avg 3 reading = 59rc.

CWF HT is applicable to most Fe+C matrix steels, except has low to zero benefit for low alloy steels with less than 0.2%C. So yes, Hitachi white#1-2 and heck their lower grade #3-5 as well, would get better result with CWF HT.

D2 because it is near worse-case scenario end of brittleness at room & below transition temperature. A sharpened iron bar (or bar made out of gummy bear or rubber) would be brittle when freezed with LN2. Thus far CWF weaved-matrix LN2 frozen blades performed extraordinary well (I haven't able to establish a unbroken baseline/control conventional ht blades yet).

A good read for many of you - http://www.msm.cam.ac.uk/phase-trans/2004/Tempered.Martensite/tempered.martensite.html

From Table 2: Stored energies of a variety of microstructures
you can see how much 'stored energy' in martensite. That's right folk 'a loaded spring'! Now try to compress it (thermal contraction) with LN2 - normal martensite matrix would crumble even by small impact load. But but the D2 blade in video survived

 

[Cobalt]

if you run a std HT sample like yours and do the same test that would be a good reference. Same steel, same profile and grind, different HT. That would be telling.

 

[BluntCut MetalWorks]

Conventional ht tempered 65rc
Tested - D2 blade failed nail cutting with blade at room temperature.
Tested - D2 blade failed nail cutting with blade at LN2 temperature.

Tested - M2 blade failed nail cutting with blade at room temperature.
Tested - M2 blade failed nail cutting with blade at LN2 temperature.

Tested - M4 blade failed nail cutting with blade at room temperature.
Tested - M4 blade failed nail cutting with blade at LN2 temperature.

Tested - O1 blade PASSED nail cutting with blade at room temperature.
Tested - O1 blade failed nail cutting with blade at LN2 temperature.
.... private data.

Untempered conventional ht at 65+rc blades = not testable, especially for high alloy steels. So at some point, I stop wasting time & $. It would be cool to see others succeed or at least failed attempts on their dime.

Keep in mind though - even after CWF Ht is published, it doesn't mean your 67rc D2 blade as equal/less/more as BCMW because of different processes(if any) taken prior to CWF HT.

if you run a std HT sample like yours and do the same test that would be a good reference. Same steel, same profile and grind, different HT. That would be telling.

 

[Cobalt]

$@&%&$#(@*$%^&$*#@(#*%%
.... private data.
.

That is what the above meant, when you make it private.

Keep in mind though - even after CWF Ht is published, it doesn't mean your 67rc D2 blade as equal/less/more as BCMW because of different processes(if any) taken prior to CWF HT
.

Ahh, so CWF is an additional step to an HT process.

 

[BluntCut MetalWorks]

Cost of data acquisition is high => auto-private unless selective-sharing.

Right! CWF HT is a hardening step, which mean this step could be use among many steps per user's HT processes. E.g. for aebl, cwf ht could be the only step. And for 52100 could involves normalized step+grain refinement steps+cwf ht.

That is what the above meant, when you make it private.
...
Ahh, so CWF is an additional step to an HT process.

 

[Cobalt]

almost like a case hardening process where you change the properties of the surface of the steel to a certain depth?