Thermacycle : Researching Metal Treatment

Status
Not open for further replies.
N

nullack

Joined
Nov 17, 2008
Messages
243
Gents thanks again for the thoughts on surface treatment. Ive ruled that out now and am looking more deeply into cryogenics and heat treatment.

Metal Science Services is related to Angel Sword and they have a trademarked metal process they call Thermacycle. They say that university tests showed a 420% increase in wear resistance for 52100 when treated at -310degrees F.

http://www.metalscience.com/services.php

http://www.metalscience.com/techinfo.php

http://www.angelswordstore.com/index.php?option=com_content&task=view&id=37&Itemid=70

They offer both a standard treatment and their thermacycle trademarked treatment. Both involve a -300F cryogenic treatment.

Apparently thermacycle is patent pending so when its issued we should be able to have a look at what the process is. It must be a more involved treatment given both standard and thermacycle happen around the same temps.

Angel swords claim they make the toughest, high hardness swords in the world.
 
Many claims have been made for cryogenic treatment.I'll only agree that it reduces the amount of retained austenite. Other claims have not been substantiated to my satisfaction.There's much hype in that business !!
 
Sadly, nowadays most any business that is trying to sell a product will tell you that their process is way better than the rest. They usually back it up with quasi-scientific jargon, like "420% increase in wear resistance". They don't say what makes it better, or back up the claims with any real numbers or comparisons to other processes. An article or study that claims a benefit for a process in general (not related to any sales) is far more likely to be of some accuracy.

Salesmen have been claiming magical increases in everything from a laundry detergents cleaning ability, to steel hardness and wearability, to penis size....."all for $19.95....but wait, if you order in the next 15 minutes..................................".
My Ex's Great grandfather had a traveling west show (he was a partner with Cody and then went on to his own show). He sold "Nowitzki's Indian Tea" at the shows. The adds (I still have some of the late 1800's add material) claim it cures almost everything including consumption, and backs the claims with the statement, "medically proven and tested".

Stacy
 
bladsmth said:
My Ex's Great grandfather had a traveling west show (he was a partner with Cody and then went on to his own show). He sold "Nowitzki's Indian Tea" at the shows. The adds (I still have some of the late 1800's add material) claim it cures almost everything including consumption, and backs the claims with the statement, "medically proven and tested".

Stacy
Click to expand...

To quote Josey Wales...

"How is it on stains."
:)

Craig
 
bladsmth said:
Sadly, nowadays most any business that is trying to sell a product will tell you that their process is way better than the rest. They usually back it up with quasi-scientific jargon, like "420% increase in wear resistance". They don't say what makes it better, or back up the claims with any real numbers or comparisons to other processes. An article or study that claims a benefit for a process in general (not related to any sales) is far more likely to be of some accuracy.
Click to expand...

Some points please:

1. By getting a patent they have to say what the process is so that another artisan in the field can understand and recreate the art. Even if the process turns out not to be significantly different from other methods of deep cryogenics its help understand the field.

2. There is engineering papers and registered astm laboratories confirming the science of cryogenic steel treatments. Some types of steel have had over a 1000% improvement in wear resistance, so 420% in 52100 does not alarm me. Besides, other papers of research verify the ballpark.

Im interested in how heat and cold treatments can make better knives. How to conduct deep cryogenic treatments. What might be done to apply it to cutlery and what might be processes that give better results.

To say that deep cyogenic treatment does nothing is akin to joining the flat earth society.....The interesting bit is about how to optimally apply it to high performance cutlery without superstition or hype.
 
If you cryo a steel like CPM154 you will get 1-2 HRc points higher hardness.
People working for various cryo companies , even members of ASM tech groups come on the forums occasionally but after being asked serious questions they disappear !! To me as a metallurgist the whole thing is an embarrassment.
 
mete said:
If you cryo a steel like CPM154 you will get 1-2 HRc points higher hardness.
People working for various cryo companies , even members of ASM tech groups come on the forums occasionally but after being asked serious questions they disappear !! To me as a metallurgist the whole thing is an embarrassment.
Click to expand...

Im tempted to label this an appeal to authority rather than a rational statement but instead Ill cover some different points with what youve shared. Its the longer route with far more time involved for me to explain, but I hope in the end you will see that rather than just trying to disagree, I am serious about improving my processes and moving forward. I will be more than happy than lick my boots and sing your praises should it make a better knife, but I dont think your right, and the research (with repeatable test results) from labs and unis Im studying has shown me the truth of it.

You claim firstly that all it might do is moving retained austenite to martensite. Frankly, when you said that I was going to ignore you because if you honestly believe that (especially being a metallurgist), you are ignoring clear, repeatable scientific findings to suit your wrong belief.

The key thing here is that it is conclusively proven that deep cryogenic treatment works on some other non steel parts. Please think about that. You have to revise your position, its clearly wrong. If nothing else was happening these other observable and measureable effects would not exist.

Research (such as Role of Eta-carbide Precipitations in the Wear Resistance Improvements of Fe-12Cr-MO-V-1.4C Tool Steel by Cryogenic Treatment; Meng, Tagashira, et al, 1993) shows that precipitation of fine carbides in tool steels is the primary factor in far greater wear resistance than additgional martensite from retain austenite. It is conclusively proven deep cyrogenic treatment increases the number of small carbides. Another paper is Microstructure of cryogenic treated M2 tool steel, J. Y. Huang, Y. T. Zhu, X. Z. Liao, I. J. Beyerlein, M. A. Bourke and T. E. Mitchell, Materials Science and Technology Division, Los Alamos National Laboratory.

Now you say in your second post that it doesnt make much of a difference to hardness. It seems to me, and I hope Im wrong, but you want to "test" me by throwing me red herrings rather than to have an open and honest discussion about how to improve treatments for our knives. Cmon, please lets be fair dinkum. This is a straw man tactic.

I didnt say it was a substitute for quenching. I was communicating it improves wear resistance in some materials. Im personally most interested in 52100, and in study after study I see deep cryogenic treatment improving wear resistance by over 400%. In a knife Im not so concerned about stress releief but that benefit is there too. Deep cryogenic treatment is an addition to proper heat cycle profiles.

The treatment has however been noted to deliver more consistent hardness values from different test samples on the work.

Sincerely
 
nullack said:
and in study after study I see deep cryogenic treatment improving wear resistance by over 400%.
The treatment has however been noted to deliver more consistent hardness values from different test samples on the work.
Click to expand...



Would you mind sending or posting the studies you are referencing? Usually it's the onus of the claimant to prove their claim, not for someone to be baited into a contrary position to have to defend their view as the information continues to be presented. If you've found studies and scientific claims to the contrary, I'd like to see them - I'd like to make the best within my means, as well!
 
nullack said:
Are you interested in adding something actually worthwhile? Cmon.....
Click to expand...

basically.....put up or shut up

whom do you work for?

lets see your data, so we can decide for ourselves

like has been said, the burden of proof is on you

I apologize for the harsh tone, but like mete has said, this topic comes up about ever 6 months. Someone comes in extoling the virtues of cryo, usually because they have some vested interest in a cryo treating business. Usually the topic ends with, "I know it works, I just can't say why or how, and I can't give any quantifiable data"
 
Last edited:
Matthew Gregory said:
Would you mind sending or posting the studies you are referencing? Usually it's the onus of the claimant to prove their claim, not for someone to be baited into a contrary position to have to defend their view as the information continues to be presented. If you've found studies and scientific claims to the contrary, I'd like to see them - I'd like to make the best within my means, as well!
Click to expand...

I already nominated three references but to add to it:

Test Results: Percent Increase in Wear Resistance After Cryogenic Tempering

52100 - 195% @ -110F and 420% @-310F

R.F Barron study results, Louisiana Polytechnic Institute

http://www.cryoeng.com/documents/ColdCuts.htm

F. Meng, K Tagashira, R. Azuma, H. Sohma, “Role of Eta-carbide Precipitation in the Wear
Resistance Improvements of Fe-12Cr-MO-V1.4 Tool Steel by Cryogenic Treatment” Muroran
Institute of Technology, Department of Mechanical Engineering, Mizumoto, Muroran, Hokkaido,
050 Japan

Please note, Busse is quoted as saying 'Grain structure and carbide distribution, are the keys to great performance NOT Rockwell hardness" which only adds depth to the importance of this paper. Interestingly Busse also uses deep cryogenenic treatment.

Rivero, I.V., Ruud, C., “Residual Stresses and Patterns in 52100 Bearing Steel: Preliminary
Analysis of Strain Hardening vs. Microstructural Transformation by XRD Analysis,” Lubrication
Engineering, Oct. 2002, p. 30 - 39

Collins, D.N., “Deep Cryogenic Treatment of Tool Steels – a review,” Heat Treatment of Metals,
23, (2), p. 40, 1996.

Collins, D.N., “Cryogenic Treatment of Tools Steels,” Advanced Materials and Processes, p. H23,
12/98.

Reitz, W, Pendray, J. “Cryoprocessing of Materials- A review of Current Status” Materials and
Manufacturing Processes – 09/2001
 
SShepherd said:
whom do you work for?
Click to expand...

I am in independent engineering consultant, my business has no vested interests. Besides, knives are a hobby not an income for me.

I already provided three references, and have again provided more following Matthews request.

An equal conspiracy theory could be that people trying to dismiss it have vested interests in keeping it exclusive. Busse uses cyro, but wont detail the thermal profile of his processes publicly.

Really, tens of millions has been spent by tooling companies on deep cyro because they want to save production costs, oh, and NASA, and also arms manufacturers especially in missiles. That scale of money isnt spent on snake oil.......

Once we get over this doubter/backwards/sacred cow hurdle some of you have, Id much rather share info on how to optimise the profile for knives as people like Busse arent talking. Thermal cycle profiles are exacting and the importance of getting it right is arguably more important than arguments about d2 vs 52100 imho.
 
The link you post is almost of no value, as it's presented less as a clinical study and more as conjecture. However, here's a link to the first document you site... again, their findings are not really completely conclusive, but they do present an interesting insight:

F. Meng, et al

As I get more time I'll peruse this stuff - certainly good reading! Thank you, and welcome to the knifemaker's area of Bladeforums!
 
Respectfully Matthew I dont agree on your first point about the efforts by the Lousiana Polytechnic Institute as being conjecture. Such institutions arent about that, and your free to replicate their tests :) Replication is a big part of these types of papers.

Im also not sure what you dont find not conclusive about the small carbides conclusion, lets have a look:

5. Conclusion
(1) Cryogenic Treatment increases wear resistance dramatically, especially at high sliding
speed. The specimens after cryogenic treatment show a minimum of wear rate.
(2) Unlike cold treatment, cryogenic treatment promotes preferential precipitation of fine n-
carbides.
(3) The formation mechanism of n-carbides is supposed to be as follows: iron or substitutional
atoms expand and contract, and carbon atoms shift slightly due to lattice deformation as a result
of cryogenic treatment.
(4) The mechanism that cryogenic treatment contributes to wear resistance is through the
precipitation of fine n-carbide, which enhances strength, and toughness of martensite matrix,
rather than the removal of the retained austenite.

So basically its shows why Mete is wrong about it being just retained austentite going into martensite. Its conclusive proof about wear resistance and toughness being improved through the process and how it actually occurs.

But please, do some research yourselves. Goto a library and grab lots of papers because there has been allot of discussion and scientific research on this. Best of all, try some tests yourself.
 
I'm not refuting the effects of cryogenics on more complex steels, btw. Most of the higher alloyed stainless steels we work with in knifemaking will benefit from cryo treatment immediately after quench.

I'm not refuting the findings of LPI, either... I just know that showing me the conclusions without showing me the whole study can easily be used to advance one side of the view, without giving the whole story. As soon as I find the whole study, I'll get back to you.

Thanks again, nullack.
 
Status
Not open for further replies.
Back
Top