Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations IDS on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Cryogenic Treatment - Technical Information 3

Status
Not open for further replies.

mewhg

Mechanical
May 13, 2002
123
In reference to my previous post on 'Cryogenic Treatment effect on Hardness' can someone point me to some good reference materials on cryogenic treatment? I know there is a reference to a paper in my "Physical Metallurgy" Book that I will track down.

Metman, I am especially interested in your comment: <<Transformation to Martensite is not time dependent rather it is only temperature dependent.>>

Thanks again,
Bill
 
Replies continue below

Recommended for you

unclesyd - we are drifting a long way off topic but the reason for the outdoor storage of Cast Iron engine blocks was intended to improve machining. Machining was in fact improved but it had nothing to do with the temperature, the cast iron parts straight from the foundry often had burnt in sand on the surface which caused severe wear of the cutting tools. Outdoor storage caused rusting of the surface forming a layer of loose scale containing much of the burnt in sand, this rust scale was much more easily detached and tool life improved dramatically.
 
Carburize, Continueing(sp?) off topic, would not the "thermal cylcing" from weather extremes also have a stress relieving effect to stabilize distortion to some degree. This is what I was told why Henry did it but not to challenge the reason you gave.

Frederick, Thanks for your reply but what about the "A". Is it A Society International or American Society? It only stands to reason that the M now stands for Materials and I was being a bit facetious about some still calling it American Society for Metals even though it really is still happening via our local chapter. Sorry to nitpick but maybe when we get the official rendering, the referenced company will edit their blurb if necessary to clarify an already murky subject. People who are not familiar with our creed need to know who are these legitimate organizations/societies that corrobarate or challenge certain claims.

I have read a good portion of your link but have not had time to read as much as I would like. Maybe I should stop rambling here to gain some time. I must say that this is very interesting and I admit to being one of those who has been saying, "if you can't support it scientiflcally, then I have some serious doubts." The link gives some persuasive arguments (I am surprized magnetizm was not mentioned alongside gravity) but I still hope to find, when I have finshed reading, of some more definitive examples in addition to those given. So far I am impressed with your treatment of the subject and the treatment of the link you have provided.

 
There are lots of myths about "ageing" or "weathering" of castings and I tend to think the surface corrosion a helping to scale off the burnt in sand has the most logic to it. I don't think that the temperature range which would occur during storage, perhaps in the most hostile environment down to about -40, would have any microstructural effect on a cast iron.
 
Regarding ASM International - the ASM no longer is an abbreviation. Since the society publishes information on materials other than metals, and does so in countries other than the USA, the name was changed to reflect these facts.

As stated above, TWI is another example. Two others are SAE International and ASTM International. The world is a much smaller place...

Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
 
Frederick--You mentioned that cryo processing has been shown to enhance the performance of cast iron brake rotors. As a former brake supplier metallurgist, I am interested in any documentation you may have on this. I have never seen anything published .
 
RE: Weathering Castings.
I know that all the major car makes did this and also the makers of machine tools. One of my customers (an Indy car engine builder) tells me his father used to bury engine blocks in the back yard for years to "stabilyze" them. Jim Birks, an early NASCAR racer and a Indy 500 racer told me that engines he took out of junkyards in Northern Illinois made better, longer lasting racing engines than when he started with a factory new block. He tells me that one engine in particular was excellent. It was the one that was "ruined" when the storage shed burned down around it at the junk yard. That is why he started investigating cryogenics with the help of a metallurgist at the Rock Island Arsenal. That led to him starting our company. No data here, just experience.

RE:ASM
I will make appropriate changes to our website as time allows. It just goes to show how things we "know are true" may not be. Whatever we call it, ASM is a great organization.

SWALL:
I doubt if there is much published. The US Postal Service has specified treated brakes in Maintenance Bulletin V-03-00. Greening Labs has tested treated brakes against untreated brakes in private tests and found increased wear resistance. We've been treating racing brakes and pads for 25 years. We have numerous police departments that purchase brakes from us and have increased their milage between brake changes considerably. I hesitate to publish names of my customers for obvious reasons, but if you will contact me I can give you specific examples of fleets where the average milage between brake changes jumped by a factor of two to four times. (My website is listed in a posting above, and I don't feel it appropriate to keep putting in a thread, too much like advertising.) Although this is not a published scientific experiment, it is an observation based on multiple vehicles before and after that shows significant change. The results are also very repeatable. It boggles my mind that when faced with this evidence, government and other fleets resist using this process. For instance, we calculated that on the 70,000 vehicle fleet the State of California has, we could save them $22,000,000/year. Even Arnold can't seem to force them to do that. This is a subject for a whole different thread in another forum about why organizations forgo huge savings. I guess I am rambling again.

The upshot on brakes is that the microstructure of most common brakes is a pearlitic. Cryogenics should have no affect on it if all cryogenics does is convert austenite to martensite.

 
It seems that the target is hard to define or we have found it and it is us.

Back to old Henry. Having worked with a metallurgist that worked for Henry in the late 20's and 30's he mentioned several times that Henry wouldn't give you the time of day if he thought it might give you some technical advantage.

Fredrick,
Glad that the process of thermal treatment, sub atmospheric, has been properly named. Also agree that the compilation of known facts for the cryo-processing is underway.

Having been made aware of property improvements of metals by different cold treatments at the onset of my career in materials in the early 50's and then in the latter 50's introduction to the cryo process, I been an avid experimenter, somewhat Edisonian. The initial problems with testing were with the availability of the LN2 or other liquified gases, you couldn’t find them at the corner store and what you could get was extremely expensive. Our first onsite test were with the condensate off an LH2, Air Force surplus trucked from California, unloading line to a vaporizer.
As stated previously we achieved several orders of magnitude in the wear properties of small tools used in the manufacture of extrusion nozzles or spinneretts. We were also able to stabilize very close tolerance rotating tool steel components used in our process by cryo treatment, didn’t happen at -40°F, instead of multiple tempers.
Here is the rub or what might be the lack of published information by people other than the people who provide the services. There are several applications, metal and others, than I wouldn’t comment on due to the proprietary nature of the applications. As we had an LN2 facility for many years this knowledge is held in house and not being disseminated This is true in other companies as well.
 
Frederick--In my experience as a brake sytems metallurgist, one of the big variables in rotor and lining performance is the linings themselves. Even linings from the same supplier and same compound can vary tremendously. As far as testing, a brake dynamometer could very quickely show if cryo treatment was of any benefit.
 
I've been involved in a similar controversial topic, high does ion implantation. As with the cryogenic treatment, for a long time people knew it worked to increase wear resistance (and other properties, even corrosion resistance), but did not quite understand why. So they made up reasons. Since nitrogen was the most common element implanted, they came up with the view that the implantation hardened the surface by forming nitrides. Nice try, but 1) you get better performance implanting with inert gases; and 2) the nitrogen is found in only the first 0.1-0.2 microns, whereas the effective case depth is closer to 10 microns. There also was the theory that the implantation added compressive stress the surface, which gave it better wear characteristics. So, we used glancing angle x-ray diffraction to measure the change in stress in implanted surfaces. We found no evidence that an increase in the compressive stress had any effect on wear resistance.

The Russians finally solved the problem by doing the obvious -- looking at the surface beyond the depth of penetration of the ions. They found the structure greatly altered, down to depths of 200 microns or more. Within the "case depth" region, i.e., the depth to which the improvements were known to extend, they found large changes in both the volume and character of dislocations. It's theorized that the changes are caused by either diffusion of dislocations formed in the implanted region, or are created by high strain levels cause by the implantation. Both theories predict that ion implantation would not improve the wear resistance of aluminum, which is in fact the case.

The bad news is that despite over fifty refereed journal papers supporting the Russian work, there are still proponents of the technology disseminating the previously-disproved theories as to why it works. The effect is to make is appear to be some sort of magic, and this makes it very difficult to gain support from serious people with serious money. I suspect the same is happening in the cryo treatment field. You can show people extensive data on wear performance of cryogenically-treated brake disks, but until you can explain why the process does what it does, backed by solid experimental data published in refereed journals, and accepted by the cryogenic treatment community, you'll have problems expanding the business.

Jim Treglio
Molecular Metallurgy, Inc.
 
ASM
I talked with ASM, and they confirmed that the official name of the organization is "ASM International", and that the ASM has no official meaning. They also confirmed that there was a progression where the M stood for metal, then material, and finally now has no meaning. I made changes on our website to reflect this, I hope I got to all the pertinent places changed.

I agree with Jim Treglio that not being able to explain why the process works is a handicap, and thqat attempts to explain citing ill informed theorys as fact really make things worse.

Swall
We, and others have had dynamometer test done by Greening, and the results are usually the same, increased wear resistance with no other changes in braking parameters.
Linings do vary tremendously. This aways makes a trial run with a potential customer a nail biter as they rarely will test on multiple vehicles to assure the results are not outliers. But I have customers who keep careful records on their vehicles and have been using our brakes for over 3 years with consistently good results. They do have an occasional problem that is usually traced to the pad, but they had that with the non treated brakes also.

unclesyd
I agree that there are a lot of companies that keep silent about their use of cryogenics. A lot of them are my customers who don't want to reveal why they have such a good product. Is ther any more you can reveal about your efforts in the early 50's that I can put in our recorded history of the process? For instance, what made you start experimenting?

By th way, I just reveiwed some interesting abstracts of papers for the ASM Heat Treating Conference on Cryogenics. I hope that I can get them into the schedule.
 
Hello.

I am a newby to this website and am looking for technical data in regard to Deep Cryogenic Processing. I am researching this industry in regard to its real validity and not someone trying to sell something to me.

Thanks.
 
Here's one for you researchers:


Enter the site and look at the main menu. This fellow is advertising a cryo treatment for saxophones. Says it does wonders...hhmmmmm...

What do you think (as metallurgists)??? I know what I think as a metallurgist AND a saxophone player! <grin!>

~NiM
 
NickelMet- I bet that Fredrick and the other real researchers fo cryo treatment love websites like that.

Saxgourmet said:
"As tone holes are drawn from the body, as the bell is shaped over a mandrel, and as posts are soldered, the natural lattice of atoms in brass is disrupted, causing internal friction. The natural structure of brass is such that the atoms line up in perfect rows that are densely stacked atop one another. During the manufacturing process, this alignment is disturbed as the atoms are dislocated. The metals ability to resonate is diminished so that only the strongest harmonics of each pitch are transmitted."
 
NickE:

I have been playing for 25+ years and this has got to be the best "snake-oil" sales pitch I have ever heard for making a saxophone sound better.

~NiM
 
NickE is right.

Sometimes it is better to be silent and be thought a fool than to open ones mouth and remove all doubt. Web sites like that one only make it harder to make progress with cryogenics. The process really is so good there is no reason to lie about it. I really wonder how they get down to -400F with nitrogen.

The problem here is another salesman saying sales things. It is generally accepted that cryogenic processing does increase the sound quality of metal wind instruments. That being said, what makes a pleasant sound is very highly subjective. In another culture, the affect of cryogenic processing could be negative instead of positive on instruments.

Cryogenic processing does change the vibrational nature of metals. My research (which is admittedly crude) on the subject shows that resonant frequencies are reduced or eliminated, giving a more pure tone.


 
Frederick:

Thanks for the information. Admitedly, I've never played a "cured" saxophone. And maybe - proven through research like you're doing - there is a cleansing of the tone. But, in my experience as a musician, it still comes down to the mechanical condition of the instrument and the ability of the musician. And, it ultimately comes down to the audience and their discerning taste. (Most probably can't tell the difference between Kenny G, Dave Koz, or John Coltrane playing sax. They only know a sax is being played.)

You are totally correct on the sound being totally subjective. I can't see such an improvement in the tone being able to be noticed in a concert hall, an open air performance, or other such occasion. But, for those of us that are studio musicians, there may be good application to have a cleaner tone, especially in this digital age, for recording purposes.

So, I don't disagree with anything you or NickE is saying. I do wish there would be more "truth in advertising" but we all know that sales pitch means everything. (Remember the "snake-oil salesmen" of the old west...and of today.) It is just too bad that certain types use fact and fiction to sell things, not realizing there may be more truth to find out.

Ah well, I'll sit here with my LA Sax and my vintage Selmers, playing "Night Train" and such, enjoying the tones that have made those types of horns famous over the years. And I'll let the researchers like you do your thing, and maybe someday let the cryo treatment cleanse my horns.

Good discussion ... great information ... thanks everyone!

~NiM
 
Just an example of "cold treatment" which solved a problem.
Here in Australia it is usual for high nickel steels to be case carburised to give high core strength. These steels invariably have retained austenite in the case. We had a situation with case carburised pins manufactured from a high nickel steel. They were developing circumferential cracks after grinding. This was solved by a cold treatment prior to grinding.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor