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Discussion Starter #1
There seems to be some confusion about the need for cryo treatment for performance rotors. I am not an expert but do haves some knowledge of the treatment. Some of us like the appearance of the cross drilled slotted rotors. They also like the idea that they dispate heat better. The trouble lies in during this process of drilling holes all over the rotor and milling slots greatly weakens the rotor. What can you do to assure the maximum strength and safety for your brake rotors?

First you can start of with a quality rotor. A common process is to pour or cast rotor using a short grained metal in a gravity settleling process. The problem with this metod is it leaves micro pockets and fissures in the casting which make them weak. By starting with a better long grain casting you can alighn the grains, reducing the pockets and fissures. Next is to compact the grains to eliminate any remaining pockets. This is done by Cryogenetics.

In the Forum there has been some arguement over the value of the cryo treatment. I'm sold on the process and own a set myself. Of couse it cost more. About $50 per rotor more. As to the need for the cryo treatment I asked Pete what he thought of those who said it was a waste of money..including Baer Brakes:

"Anyone that has any interest in educating themselves on liquid nitrogen cryogenic processing can simply do a couple of things: go to the library, take a master's level course in physics and metallurgy or simply educate themselves via the internet. Hal Baer is certainly entitled to his "opinion", but I can assure you that there is not a single strand of truth in the statement that there is no "hard data". There is more hard scientific data that it is beyond description that "anyone" would make the comment....."show me the data". Every single vehicle that runs at NASCAR NEXTEL Cup,, etc runs cryogenically treated rotors. In fact, most of the entire drive train has been cryo-treated." Pete Raimondo

Auto Racing is a major user of Cryogenics:

Extremely low-temperature treatments boost the performance and service life of critical components.
By Roger Schiradelly and Frederick J. Diekman*​
R​
acing pushes engine and drive train components to the absolute limits
of their durability. Extending those limits means more speed, better safety, and more races won. For this reason cryogenic processing is becoming a necessary part of the manufacturing process for racing components. This racing experience will serve as an example to manufacturing industries — now similarly engaged in their own competition against manufacturing costs and waste, and the challenge to provide high quality products with superior performance. Using extremely low temperatures to make permanent changes in metal. Cryogenic processing is not the typical -84°C (-120°F) cold treatment most heat treaters use. It essentially involves exposing materials to temperatures below -184°C (-300°F). If done correctly, it creates a permanent change to the material that alters many wear characteristics.

The concept of changing metal through the use of low temperatures is relatively new and not well understood. Yet it is certain that exposure to very low temperatures does make permanent changes in virtually all metals and to some plastics. Observed changes include:
• Increased resistance to abrasion
• Increased resistance to fatigue.
• Transformation of austenite to martensite in ferrous metals.
• Change in vibrational damping.
• Anecdotal evidence of changes in heat transfer.
• Stabilization of metals to reduce warping under heat, stress, and vibration. In practice, cryogenic processing affects the entire mass of the part. It is not a coating. This means that parts can be machined after treatment without losing the benefits of the process. Additionally, cryogenics apply to metals in general, not just ferrous metals. For many years, it was assumed the only change caused by extreme cold was the transformation

CRYOGENICS

HEAT TREATING PROGRESS
Racing applications Cryogenic processing is currently in use in every form of racing imaginable. It is used in virtually every class of NASCAR racing, IRL, CART, NHRA, IHRA, SCCA, IMSA, and ARCA, not to mention tractor pulls, go-karts, motorcycles, boats, and even lawn mower racing. Controlled Thermal Processing (CTP) has even done a fair number of axles for soap box derby cars. Over half of the cars competing at any given NASCAR NEXTEL Cup race run parts that are cryogenically treated by CTP alone. Cryogenic processing can have a positive affect on virtually every engine, transmission, and drive line part, as well as many chassis parts.
The challenge of designing engine and chassis components that will survive long enough to win a race, but will not have any excess weight as a consequence. Put in too much mass, and a car will be slow and handle poorly. Make components too light, and they will not survive the race. There is always this delicate balance: weight versus reliability. The great thing about cryogenic processing is that it allows an increase in durability without an increase in weight or major modifications to component design.
This is especially true during road races and endurance racing, where brake rotors can get so hot they glow visibly at night. Cryogenic processing can be applied to both rotors and pads. The net result is two to three times the life of untreated components even under severe racing conditions. As a side benefit, the rotors are less prone to crack or warp.
Postal Service specifies cryogenic processing for their rotors and is experiencing up to three times as many miles as they were getting on the unprocessed rotors. Similarly, many police fleets are starting to adopt treated rotors and pads. They, too, are experiencing large maintenance savings on both parts and labor. part of their production.
 

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Discussion Starter #2
I couldn't fit all my information in that one post. Here is some more data to support the need for cryogenics. I know the naysayers will never take the time to read all of this information. But for the newcomers really wanting to make a safe and intelligent choice..this information may be of help in making your choice.
Bob

ARTICLE

By John DeGaspari, Associate Editor
Improving the wear resistance of steel can amount to found money, particularly in industrial uses such as stamping dies and machine tools.
In the operation known as quenching, steel is heated and then brought back to room temperature, either gradually or abruptly (using air free or forced, water, or oil). Quenching makes steel harder, improves mechanical properties, and increases wear resistance. Yet some tool and die makers believe that the proven benefit of extended wear life of conventionally heat-treated steel parts can be further enhanced by tempering at cryogenic temperatures.
Prior to quenching, steel is relatively softer, allowing it to be wrought and drilled easily. Cold-worked steel is in the austenitic phase, in which the microstructure is characterized by large, coarse, and irregular grains. (According to information published by the American Iron and Steel Institute, about 70 percent of stainless steels produced are austenitic.)
Quenching converts most of the austenitic microstructure to the martensitic phase, which is finer and denser. Martensite, the chief component of quenched steel, consists of hardened carbides that provide the higher hardness and wear resistance.
The grain structure of steel alloy before and after cryogenic tempering. Lab tests demonstrated that cryogenic tempering completed the transition from austenite to martensite, improving the alloy's wear resistance.



Although conventional heat treatment results in harder steel, it still leaves room for improvement. For one thing, quenching does not quite completely transform the austenite to martensite, leaving a residue of the softer, coarser microstructure. Also, martensite, although much harder, is also more brittle than austenite.
Some tooling experts believe that an additional treatment involving cryogenics can help complete the transformation to martensite and dramatically improve wear resistance in a range of steel alloys.
The idea of treating steel cryogenically to improve wear life has been around at least since the 1940s, according to Randall Barron, an ASME Fellow and professor emeritus in the Department of Mechanical Engineering at Louisiana Tech University in Ruston, who is also a consultant on cryogenics.
Better results were obtained in the mid-1970s by cooling slowly with cold nitrogen gas, followed by a mild tempering, which avoided thermal stresses and brittleness, Barron noted. Some aerospace companies have used cryogenics to treat steel parts that are subject to high wear, he added.
Controlled Cooling
Cryogenics has attracted the interest of others who want to improve wear resistance in wider applications. Les Davey, the owner of Silver Bullet Machine & Tool Inc., a tool and die maker in Windsor, Ontario, became intrigued with the idea of using cryogenics to boost wear life when he noticed that cutting tools cryogenically treated in a local machine shop lasted three to four times longer than normally expected.
Davey describes his process as a tempering operation that incorporates cryogenics, with some differences from previous deep-cold treatments of steel. Hardware consists of a combination of oven and freezer, and includes a tower of liquid nitrogen. The process itself is automated, with temperatures and duration programmed into a computer. The DTT process subjects parts, all of which have already been heat-treated, to temperatures generally ranging from about 600°F to -300°F.
Steel parts are exposed to precise temperatures for specific periods of time. The program regulates the temperatures in a controlled, step-wise fashion. Davey said that he developed specific recipes after observing how different steel alloys were affected by various tempera-ture exposures.
He believes that the tightly controlled recipes are what differentiate his process from standard cryogenics, which may involve simply lowering the temperature gradually to -300°F or so and holding it there for a time before letting the steel warm to room temperature. The key, he said, is "the temperatures we go to, how long we stay there, and how quickly we get there."
Davey noted that Dynamic Thermal Tempering involves "deep cryogenics" for extended soak periods. "We have data from a number of studies that indicate a significant difference between -120°F and -300°F treatments," he said. The evidence favors deep-temperature treatments, he added.
A technician polishes discs of 4340 and 9310 steel alloy, comparing conventional quenching results and quenching followed by cryogenic tempering.



He also added that the treatment penetrates through the steel. He has tested the process on various blocks of steel to see how long it takes for the temperature to penetrate from the surface to the core. One treatment lasts for the life of the part. "Once tools are sharpened, the treatment is always there, because we are actually changing the properties of the steel, rather than solely its surface," he said. "The entire process, from start to finish, requires that we have the tool for three days," Davey said. "Once we get the temperature down to deep freeze, it has to sit there and soak for a long time. Achieving the proper temperature and holding it for a prescribed period of time results in the benefits of the process being imparted to the steel tool." The temperature is then brought back very slowly to ambient. Some materials require tempering; parts are heated to the required temperature and then cooled to ambient. In many cases, such heating and cooling cycles are repeated once or twice. Temperature is rigidly controlled during the tempering cycle as well.

Makes sense doesn't it?!!:yup:

 

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Discussion Starter #4
newton said:
hey if pete says it AND you read it on the internet, it must be true
First consider the source of the information on the internet. Just like you do when you come to this Forum. I considered my information to be reliable sources and congruent with my other readings. I'm sure you read these articles and are much more knowledgable regarding cryogenics..right? What are the implecations of your comments Newton?:hmm:
 

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Robert, thanks for the information. However it's a little dated. The articles you quote was written in 2001.
http://nitrotemp.com/page4.html

This information is a little dated. technology marches on. Two of the companies I represent are major internal engine parts supplies to the majority of the Nascar engine builders. Comp Cams and Mahle Motorsports. Mahle also make pistons for the turbo Audi ALMS cars. Comp supplies 99% of the camshafts and valve spring to the Cup, Busch & Truck teams. Today none of these parts are cryo treated. These manufacturers have tried and moved on mostly to new materials, alloys and manufacturing process'. The only people you'll find really touting cryo treating are the cryo treaters.
Rather than theory I'd like to see wear data on a treated rotor vs a non-treated rotor,that's all.
Scott

PS there is no "t" in cryogenics;)
 

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Discussion Starter #6
HaveBlue said:
Robert, thanks for the information. However it's a little dated. The articles you quote was written in 2001.
http://nitrotemp.com/page4.html

This information is a little dated. technology marches on. Two of the companies I represent are major internal engine parts supplies to the majority of the Nascar engine builders. Comp Cams and Mahle Motorsports. Mahle also make pistons for the turbo Audi ALMS cars. Comp supplies 99% of the camshafts and valve spring to the Cup, Busch & Truck teams. Today none of these parts are cryo treated. These manufacturers have tried and moved on mostly to new materials, alloys and manufacturing process'. The only people you'll find really touting cryo treating are the cryo treaters.
Rather than theory I'd like to see wear data on a treated rotor vs a non-treated rotor,that's all.
Scott

PS there is no "t" in cryogenics;)
Prig!!:D


Most of that info is dated 2001. Most of the Ebay rotors are not even up to 2001 standards. These new alloys aren't offered on any of these $200 rotors so the Cryo treatment still applies.
 

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RobertCTS said:
Prig!!:D


Most of that info is dated 2001. Most of the Ebay rotors are not even up to 2001 standards
HUH?! Jess it's like dealing with a 5 year old.

Try this.
The valve springs in Cup cars used to break... alot. Cryo treating was tried as a bandaid. The real problem, harmonics was solved with lots of real R&D. Springs are now made from "super clean" alloys, drawn in an ovate shape and wounde in a beehive configuration. Pushrods have also been increased on diameter to stop bending and pogo-ing, which transmits harmonics into the spring. Long held "absolutes" like valvetrain weight have been thrown out. Only the weight on the valve tip it's self is keep light, everything else is designed for stability in a given rpm range. The result, pushrod motors turning 9800 RPM for 4 hours. Unheard of in 2001.

My comments have nothing to do with ebay rotors only cryotreating as a dated technology.
 

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HaveBlue said:
HUH?! Jess it's like dealing with a 5 year old.

My comments have nothing to do with ebay rotors only cryotreating as a dated technology.
I think it's spelled Geez! Just playing with you HaveBlue. I have a lot more respect for you after Ody filled me in on you and your background. My brother is always correcting me and others and I began calling him a Prig.:D

HaveBlue also keep in mind these special alloys currently used by NASCAR are low production and very expensive items. Can you tell me how much the Teams are spending on these rotors? $$$
 

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HaveBlue said:
Robert, thanks for the information. However it's a little dated. The articles you quote was written in 2001.
http://nitrotemp.com/page4.html

This information is a little dated. technology marches on. Two of the companies I represent are major internal engine parts supplies to the majority of the Nascar engine builders. Comp Cams and Mahle Motorsports. Mahle also make pistons for the turbo Audi ALMS cars. Comp supplies 99% of the camshafts and valve spring to the Cup, Busch & Truck teams. Today none of these parts are cryo treated. These manufacturers have tried and moved on mostly to new materials, alloys and manufacturing process'. The only people you'll find really touting cryo treating are the cryo treaters.
Rather than theory I'd like to see wear data on a treated rotor vs a non-treated rotor,that's all.
Scott

PS there is no "t" in cryogenics;)
Finally! A voice of reason and source of good information :thumbsup:
 

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RobertCTS said:
I think it's spelled Geez! Just playing with you HaveBlue. I have a lot more respect for you after Ody filled me in on you and your background. My brother is always correcting me and others and I began calling him a Prig.:D
DOOH! You got me there!:bonkers:
 

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from experience...

i have mine on for 20K miles w/out creo...and no stress crack or unusual wear...can't argue w/ actual conditions
 

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wratran said:
from experience...

i have mine on for 20K miles w/out creo...and no stress crack or unusual wear...can't argue w/ actual conditions
That's not the life of rotor. You could still be sweeping up the pieces. I have a piece of mind that mine are safer and will last longer.
 

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RobertCTS said:
HaveBlue also keep in mind these special alloys currently used by NASCAR are low production and very expensive items. Can you tell me how much the Teams are spending on these rotors? $$$
Robert, I'm watching the Martinsville race and remembered I forgot to come back and answer your question.
Nascar rules prohibit the use of exotic materials. (you may remember that Ray Evernham/Jeff Gordon go busted for this once). Cup rotors vary by manufacturer and track style. Most are high quality iron, with a higher silicone content for durability or chrome molly.
HOWEVER, the most important thing you have to remember is that you are working within the envelope of the Nascar mandated 15 X 9.5 steel wheel. Dependant on the track, the rotor thickness varies. They don't want to carry any more unsprung weight than necessary. So you have very thick rotors at short tracks, thinner ones at super speedways. Also the calipers vary by track. The diameter of the rotor is limited by the wheels and again varies by track type 11.9 to 12.7 inches.
Rotor rings average about 200.00 a piece.
 

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RobertCTS said:
That's not the life of rotor. You could still be sweeping up the pieces. I have a piece of mind that mine are safer and will last longer.
I have yet to see a drilled and/or slotted rotor crack or fall to pieces as you say w/normal everyday driving. If you autocrossed the car than yes you will have a problem. If you don't, I think you'll be alright.
 

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HaveBlue said:
Robert, I'm watching the Martinsville race and remembered I forgot to come back and answer your question.
Nascar rules prohibit the use of exotic materials. (you may remember that Ray Evernham/Jeff Gordon go busted for this once). Cup rotors vary by manufacturer and track style. Most are high quality iron, with a higher silicone content for durability or chrome molly.
HOWEVER, the most important thing you have to remember is that you are working within the envelope of the Nascar mandated 15 X 9.5 steel wheel. Dependant on the track, the rotor thickness varies. They don't want to carry any more unsprung weight than necessary. So you have very thick rotors at short tracks, thinner ones at super speedways. Also the calipers vary by track. The diameter of the rotor is limited by the wheels and again varies by track type 11.9 to 12.7 inches.
Rotor rings average about 200.00 a piece.
Yo HaveBlue,
You redneck. You must be posting during the cautions! I hope Tony gets beat. Brakes will fail today!
 

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Now Rob, lets be nice. Thanks for providing the info and your opinion. I think the wisest thing for anyone whos interested in new brakes is to look at the information thats out there, and then talk to someone who's an expert with brakes. Some treatments may be suitable for daily driving, while others are better if one plans to drive their car much harder, such as in autocrossing. I think it all depends on how you plan to use or abuse them.
 

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DDS rollin a CTS said:
Now Rob, lets be nice. Thanks for providing the info and your opinion. I think the wisest thing for anyone whos interested in new brakes is to look at the information thats out there, and then talk to someone who's an expert with brakes. Some treatments may be suitable for daily driving, while others are better if one plans to drive their car much harder, such as in autocrossing. I think it all depends on how you plan to use or abuse them.
Doc,
Really I think I am nice. We have a problem? Me and have blue are cool.
 

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05CTS said:
I have yet to see a drilled and/or slotted rotor crack or fall to pieces as you say w/normal everyday driving. If you autocrossed the car than yes you will have a problem. If you don't, I think you'll be alright.
Just in case, I still have my 4 original rotors stacked away...LOL
 

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RobertCTS said:
Doc,
Really I think I am nice. We have a problem? Me and have blue are cool.
I was referencing the "you redneck" comment, guess I should have quoted. As long as you guys are cool, its all good. I just didnt want to see an intellegent debate degrade into name-calling. It seems to happen way too much around here sometimes.
 
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