Myths About Cryogenics
It was hard to sell Deep Cryogenic Treatment in the early days. People just would not believe that DCT would work. So we were fed some interesting comments about us selling "smoke and mirrors" or "Snake Oil". Two metallurgists for the nation's biggest aircraft manufacturer wrote a vehement letter to ASM demanding that they write a retraction of the article I wrote for their Heat Treating Progress Magazine. So we were inundated by statements made to just make us go away. Also, there was a certain amount of logic displayed because people really had not thought much about what you could do with cold. I started making a list. Here it is.
To be fair, these are often used by people who just want you to go away and not disturb them. After all, they are the experts in their field, and they know what they are doing. If they solve the problems of their fields, they may be out of a job. Of course, if they don't solve those problems, they will be out of a job as their competition takes over their market. Increasingly, that competition comes from outside the USA where people are more than willing to provide the best possible product.
Freezing metal can't possibly change it.
We hear this a lot, even from metallurgists. The reality of the situation is that many things can happen in the crystal structure as the temperature is reduced. In fact, Martensitic transformations have been observed at temperatures as low as 4°K. (reference: Kulin, S.A. and Cohen, M., Trans, AIME, 188 (1950), p.1139) Basic metallurgy text books even give equations that describe some of the things that are happening, but since these things are not generally used in heat treating most metallurgists and engineers simply do not remember them. Another factor is that the temperature change must be fairly slow for the changes to take place.
- That can't possibly work.
It is very interesting that people say this. We have independent lab reports, research from major universities such as Illinois Institute of Technology, Louisiana Tech University, University of Trento, Italy, National Heat Treatment Center of Dublin. We have tech papers from NASA, Los Alamos, the US Army Aviation and Missile Command and many others. They all say the process works. Where is the proof of those who say the process can't work?
- We've never heard of that, so it can't be any good.
Nothing is new in the world, nor will there ever be anything new. Columbus could not have sailed to a new continent, because nobody had ever heard of it before. (Except some Vikings, but nobody listened to them. Everyone was too busy running away from them.) Also, we have to accept that there are people who know everything.
- Your competition calls it Cryogenic Tempering or Deep Cryogenic Tempering
People who use these terms were just looking for things that sound good in marketing the process. First of all, cryo processing is not a tempering process. Cryogenic tempering is a meaningless term. Tempering is defined in ASM's Metal Handbook as "..reheating hardened steel or hardened cast iron to some temperature below the eutectoid temperature for the purpose of decreasing hardness and increasing toughness." That is not cryogenic processing.
- Cryogenics is freezing dead bodies.
We hear this a lot. Actually the freezing of bodies with the intent to wake them up later is called CRYONICS. So don't worry, we won't put your parts next to either Walt Disney or Ted Williams. (By the way, Walt was not frozen.)
- If that were any good, we would have been using it a long time ago.
See the answer at #3 above. Galileo ran into this a lot. They told him that he had to stay home for the rest of his life because he postulated things that were new. Like the earth is not the center of the universe. Kind of a big time Renaissance time out for a naughty genius. Of course the penalty for sneaking away from his time out was death. That really put a stop to progress in his neck of the woods.
- Cryogenics is VOODOO Science.
They say this because we can't totally explain why it works. They totally ignore the studies by the US Army, US national laboratories, and major universities all over the world that say it does work. Recently we've noticed a lot of Chinese research into the subject. Science is based on observing things we do not understand, observing that they are repeatable, formulating a theory to explain the observations and then testing the theory by experimentation. There is nothing in scientific method that says that you cannot use something that you don't understand. If there was, THEY wouldn't let us use gravity.) If we needed to use only totally understood phenomenon, all progress would be stopped. Science does not flow neatly out of the laboratory into general use. Economics drives what is used in the real world, not some sort of jury of scientists. Cryogenic processing has proven economically desirable even if we don't totally understand it. As cryogenic processing becomes more widely used, we are beginning to formulate why it works based on experience of where it works.
- Cryogenic processing makes steel more dense.
Interesting. Let's see. It converts austenite to martensite. The martensite crystal is about 4% bigger than the austenite crystal. In order for the steel to become more dense, it will also have to become heavier to make up for the increased volume. Wow, cold fusion in every possible sense!
- Cryogenic processing changes the molecular structure of metals.
If you are not an engineer, cryogenic processing company or metallurgist, I will give you a pass on this one. But all you engineers, cryogenic processing companies, and (shame on you) metallurgists out there who parrot this had better go sit in a corner for a couple of decades. Metals get their metallic properties because they are crystalline in structure and not molecular.
- We tried that 30 years ago and it didn't work.
I like this because it implies a certain constancy to life. Everything goes along just as it was when we were children. Stick your head in the sand, and do your time in the office, and all you learned in kindergarten will carry you through life just fine.
- Your machine is round. We want a rectangular machine.
Yes, it is round. It is round because it is vacuum insulated. It is vacuum insulated because that is the best way to insulate things at -300°F. Rectangular machines have lousy air flow, have heavy structures that pull the cold right out of the chamber, have insulation that breaks down over time and is very hard if not impossible to renew. They have extensive bracing that act as heat bridges. They have huge problems with door sealing, which lets lots of heat into the chamber. Some square machines actually bend during the cycle so that doors warp open. If square were better, liquid nitrogen would be shipped in square containers, but people who handle that stuff avoid square like the plague.
Why do we persist with round machines? Because we also use the machines we sell in our own processing facilities. They produce higher profits, are more rugged, more reliable, and easier to use.
So if you want to buy a machine that will not last very long, will use liquid nitrogen like it is going out of style, will not do a good job of treating parts, and will cost you considerable money to renew door seals and may not get down to temperature, get a square one.
- If we make our product last twice as long, we won't sell as many of them.
Somebody slept through basic economics class. If you make a better product, your competition will suffer. Their volume will go down, not yours. In some cases you may sell fewer widgets, but still make more profit. More money for less work. Let's face it, if you don't make the best product for the money, someone eventually will. If you are in an industry that is complaining that everything is made overseas, take a close look and see if you are giving your customers the best possible product.
We have a lot of trouble when salesmen get involved in the decision to use cryogenics or not. Their advancement (as well as upper management's) is based on increasing sales dollars, not increasing profits. Seems to us this system has a huge flaw.
- They control the temperature in their machine to 0.1 degrees F. That's got to be good!
Look, they use the same kind of thermocouple as everyone else, so it is highly doubtful that it is calibrated that closely. Even if it were, so what? It is sensing air temperature within the machine, not part temperature. Believe us when we tell you that there will be a spread of temperatures within that machine, and it will be a lot higher than 0.1°. Also believe that 0.1°F is not critical to the process. If it were, we would have to account for the temperature of the part being processed, not the air temperature within the machine.
- They have a computer controlling their machine!
And they claim it to be an advantage. Look, the computer is just doing the same thing that a good industrial grade microprocessor based temperature control would do. There is a reason that heat treaters do not use personal computers on their ovens and it has to do with reliability. Personal computers have a bad habit of locking up at the wrong time. They are not meant for industrial environments.
- Cryogenics will make the metal brittle.
This one gets me. It has a corollary that cryogenics will make the metal too hard. I usually hear this from people who know nothing about cryogenics, but they say it with great authority. Cryogenic processing rarely makes metal significantly harder. If it does, there was a big heat treating problem. It rarely makes metal brittle, in fact it often allows the metal to bend more than it would before treatment. If cryogenic processing makes metal brittle, how come we can increase valve spring life up to seven times in racing engines? Yes, metals can be brittle while they are at very cold temperatures, but that does not mean they remain brittle when they warm up. Remember, metals get soft when they get hot, but we use heat to harden them. Also, most cryo cycles have a tempering cycle in them to reduce the effect of the primary Martensite (if any) being formed.
- Cryogenics is only for bad heat treat.
Well, it will convert retained austenite to martensite in a big way. So will cold treating to -140 degrees F. That doesn't explain why the US Army found that cryogenically treating cold treated gear metal (9310) doubled the life of the metal, or why cryogenic processing increases the life of aluminum, copper, titanium, etc. Also, consider the case of brake rotors. They are not heat treated but get a considerable life increase when Deep Cryogenically Treated correctly.
- Our tooling lasts long enough so we see no need to treat it.
This will really get you thinking, especially when you know that they are replacing their expensive tool several times a year. It would seem to me that "long enough" is long enough only when the tooling just outlives the market life of the product. Actually, we are looking for tooling costs to be optimized over the product market life.
- We can't spend any more on tooling.
What they really mean is that they can't spend any more money up front. They can hemorrhage money after the tool is made on repairs, labor, sharpening, lost production, because that comes out of someone else's budget. After all, success is measured in how little your area spends, no matter what it costs the rest of the company, right?.
- We don't believe in that.
This is not a religion.
We often get this. One very large manufacturer of plastic containers and household goods tried using cryogenic processing on the blades of their scrap grinders. Normally, they would change these blades every three months. They have been in the machine for two years now. They don't return our calls. The engineer who put them into the machine is bewildered. It would save his division a lot of money. It is his job to save his division a lot of money. They won't let him do his job because????? By the way, the newspapers have had articles about this company losing money and not making its profit predictions. Is there any wonder why?
- We don't have time for that.
But we have plenty of time to fix, remake, rebuild, etc. when the part craps out? Production delays at that point are part of someone else's budget. This excuse is also used a lot by racers. They don't have time to have a $400 set of valve springs processed so it will last a full season, but they have time to order new springs and change them every other weekend.
- There is No Research
The amount of research being done on Deep Cryogenic Treatment is extensive. The Cryogenic Society of America has established a database (which is available to anyone on the web at www.cryogenictreatmentdatabase.org/. It has peer reviewed research papers from all over the world written on the subject of Deep Cryogenic Treatment. Most of the research at this moment seems to be coming from India.
- You Don't Have Any Research To Support My Application
Yes, we probably do not have research to support the use of cryogenic processing on widgets when the relative humidity is 83.52%, and there is a blue moon, and there is a camel present. Look, if someone has researched your particular situation before you, it is probably your competitor, and your customers are probably all over at his place buying from him because they get a better product. Just shut off the light, and go home, permanently.
- Cryogenic Processing Will Not Work On (insert material name here) because there is no retained austenite in it.
Metallurgists often pull this one. They were taught that the only use of cryogenics is to convert austenite to martensite. So obviously, cryogenics will not work on austenitic stainless steels, cast iron, non ferrous metals, and such. The trouble is that it does work on these materials. We have had customers who, while observing huge savings on downtime and part replacement, were ordered by the corporate metallurgist to stop using cryogenics because "It can't work on that metal." One of the biggest uses for cryogenic processing is for brake rotors which have a pearlitic microstructure. No Austenite, no martensite.
- Cryogenics works on brake rotors because it turns the austenite into martensite.
I love this. Give the dummies (customers) something they think they understand. Look, the customers are not dummies, and some of you out there know that common brake rotors are made from pearlitic cast iron.....no martensite, no austenite. Yet we've proven beyond any doubt that brake rotors benefit greatly from cryo.
- Cryogenic processing is easy. Just drop the part in liquid nitrogen.
Dropping parts in liquid nitrogen is a good way to create cracks, metal gravel, and such. Look, the research shows that some of the good stuff you get out of cryogenic processing comes from time the part spent going down to -300F, how long it stayed there, and the time it took to come back up. If you do not control these, you are basically wasting your time. If you go to http://www.youtube.com/watch?v=yg45ILXZ26w , you will see why. In this short video made by Jefferson Labs you will see what the stresses created by dipping can do to a piece of rubber. Similar things happen to steel.
A fellow walked into our booth at the PRI Trade Show and claimed that cryogenics was a hoax because he was a scientist, he had tried it, and there was no increase in fatigue life. Upon examination, we found that this "scientist" who was a metallurgist for a major spring company had dropped a spring into liquid nitrogen and claimed that as a cryogenic process. This 'scientist' had not even bothered to read the literature.
One of our engine building customers likes to tell the story about a customer who wanted to have a crankshaft treated (before he met us) and they took it to a heat treater who dunked it in liquid nitrogen. The crankshaft cracked in short order. Actually, it cracked when it hit the liquid nitrogen. Heat treaters will tell you they know all about cryogenics, but they really know that they can get things cold by dipping them. They have no idea of what they are doing.
- We don't care that it works. We have to know why it works.
If this is so, you had better go through your plant and eliminate every process that uses things that cannot be fully explained. Start with gravity.
Knowing why it works is not essential to science. Here are a few quotes from some scientists you may have heard of:
"The purpose of science is not to obtain a proper solution of the problem discussed by philosophers, namely, what causes objects to behave as they do." Galileo, Dialogs Concerning Two New Sciences
"To establish the laws of phenomena I have not inquired into the cause one might assign to these forces" Ampere
"In order to predict what is useful to us, it will not be necessary to know the mechanism." Henri Poincare
Similar views were expressed by Newton & Fourier. (Thanks go to Harry White, who wrote about this in his upcoming book.)
- We want a coating to solve our wear problem.
People have unbounded faith in coatings. They believe that a nice gold colored coating that is .00005 inches thick will armor a piece of metal against anything because it is hard. The fact that the material under the coating cannot bear the strain means nothing to these people. Coatings are fine when you are faced with a problem of reducing friction, inhibiting corrosion, or resisting light abrasion. Listen: Coatings are like egg shells. Remember, all the king's horses and all the king's men. . . . .
- Nobody has ever blown a cryogenically treated engine.
I found this on a competitor's web site. Look, if you put two racers in a padded room and give each a bowling ball, in about a half an hour one will have lost his and the other will have broken his. (Sorry guys!) The point is that racers can break anything, and we have the fragments to prove that. Blowing an engine can be caused by many factors that cryogenics cannot address. Examples are loss of coolant and loss of lubrication.
- We can't afford to change the prints.
This came from a manufacturer of large earth moving equipment. We treated some 12.5mm drills for them which they tested and found far superior to untreated drills. They calculated that it would save them about $75,000/year on this one operation on one part number. Reason for not using cryogenics is it would cost too much to make a change. This was about 11 years ago. They've spent millions extra on that one operation since then, not to mention what they would have saved on all the other operations on that one part.
- I don't think it works.
This is a unique story. I've heard it from both the metallurgist involved and the owners of the company at the time cryogenics was initiated. We'll call the metallurgist Dr. Smith, because I haven't asked permission to use his real name. The company was a major manufacturer of firearms. Dr. Smith bought a cryoprocessor from us and documented savings of over $1,000,000 the first year on tooling. The second year was about $2,500,000. At this point, the company was sold. Dr. Smith was downsized out. I would like to see the justification for that one. Let's see, Dr. Smith, we can't afford you because you are only saving us $2,500,000/year on just one decision.
The running of the cryogenic processor was turned over to the maintenance department who promptly shoved it into a corner. When the new management asked about it, maintenance told them "I don't think that process does anything." Management got real decisive and declared, "Then get rid of it." The cryoprocessor was traded for a fork lift truck.
About a year later, the accounting department got around to looking at the tooling budget. It had skyrocketed for some mysterious reason. The company ended up buying a new cryoprocessor. You will be happy to know that "Dr. Smith" landed on his feet. He is a highly respected "mover and shaker" in ASM. I love telling your story, Fred!
- We won't use it until we are being beaten by it.
This came from a highly respected Sprint Cup team owner. He came up with this pronouncement when asked if his team would like to explore the possibilities of using cryogenics. Since over half the cars in Sprint Cup series are using parts we cryogenically processed, and they are winning, I would guess that this fellow is a little late. The trouble is, we have confidentiality agreements with some of the teams we work with, and we can't tell this guy who we work with.
- We don't need cryo treated rotors. Our OEM rotors last over 100,000 miles.
A city in Illinois came up with this. Then they claimed they can get new rotors $17.00/pair if they need them. Kudos to these cops for driving a big, heavy police car with lots of cop stuff in it so gently that they can get 100,000 miles on a set of rotors!! These guys should be used to train every cop in the nation. Think of the money that could be saved in this country. I really believe they should be forced to show their remarkable driving technique to the whole nation.
More to come.