I want to reuse my S4 stationaries for a N/A motor I'm building, and was wondering if it would really be worth it to have them treated. I'll be keeping the stock red-line and plan on 150-ish hp.





Thanks!

You will acheive lower frictional losses thru the use of REM polishing. Some shops offer a combo cryo-Rem treatment, but I have yet to see the benefits of cryo

I doubt that there will be much beyond stock stresses involved. The stock parts should do nicely.



Lynn E. Hanover

REM (i.e. Chemically-Accelerated Vibratory Surface Finishing) is definitley a proven process and I would really like to do that to a few things If I can afford it. I've read elswhere that cryo treatment of the side or oil seals(can't remember which) proved beneficial. I gues I'm just too concernd about longevity. Like you said Mr. Hanover... It's still basically within stock levels. In its fullblown glory, it could get up to 200 hp... Its just going to be one of those things that tug at me... Every time it redlines voices in my head will start chanting, *It's fatiguing!...It's fatiguing!...Ooh! Did you here that tooth chip?... Keep it up! One of these days you'll have a nice coffe grinder.* https://www.nopistons.com/forums/pub...1047683664.gif These stinking S4 internals! Why did they have to be in such good condition?



Oh well. I guess what I really want/need is more experience.

I can allways sell them to offset some the cost of upgrades. lol...





Anyways, thanks for the input!

spend the money you were going to use for cryo treating on other things like New competition bearings with the deeper oil groove.



In my opinion cryo treating is Bull ****.

i'm pretty much inline with everyone else.



you dont really need to do anything. if you're still worried, you can upgrade to the 89-91 hardened gears, or the fd gears and larger thrust bearings, more oil pressure etc

Ive read about it greatly extending the lifetime of stock brake rotors in racing classes that require them. Your thoughts on this?

arent 13b renesis stationary gears easily available, have better designed, hardenned, and cheaper than the cryo treatment?

I hear the same about brake rotors...but generally I still lean toward the side of the guy who called bullshit, a deep freeze rearranging the molecular structure? Isn't that how some mastermind criminal got through some high end locks, by super freezing and braking them with an effortless strike afterword? For those that use that service, I hope the individual performing the process isn't in the bottle that day.

I haven't tried it myself. I for one would rather buy a higher quality brake rotor to begin with if I had the option of cryotreating made in taiwan rotors vs buying mazda oem from the dealer.



If I really needed extra margin to prevent warping of the brake rotors or excess wear. I would, use ducting, find a friendlier pad, or as a last resort heat treat the rotors and surface grind the surface 5 thou deep. Atleast for heat treatment I know I'm increasing the hardness of the surface. Where as cryotreating is still wishy washy.



I know that Heat treatment changes the mechanical properties of the metal since it depends heavily on the type of microstructure was produced during the phase transformations when the material was cast and then cooled. With heat treatments you are essentially rearranging the mircostructure to give you different ratios of austenites/martinsite etc.



The reason why I say cryo treating is wishy washy bull **** that cryo treating does not influence the microstructre of the metal as it can not recrystalize the grain structure at that temperature. You change the microstructure by controlling the alloy of the steel, and then you cool the metal at a set rate. You then reheat the metal and recool to recover the mircostructure you want.



If you look at and phase treatment of any metal it is described by a euctectoid reaction. For cryo treating it shows the same composition of metals on both sides of the equal sign. Meaning nothing happens when you cryotreat. THe only way cooling changes anything is when you control the heating of the sample and control the rate of cooling forcing the material to pass through different phase regions of the phase diagram again.



Nothing happens below room temperature...



That is my view on cryo treating. I for one can think of better ways of spending the money on different components that give you more gains such as competition deep groove bearings vs cryotreating gears. The 13BREW and rx8 motors, and the racing beat hardened stationary gears I'm sure are all heat treated to get an increase in hardness, not cryo cooled. They mean even be nitrided for even more hardness.

5th paragraph, 7th word... should've been transition, not treatment. I should've proof read the post before clicking submit...

The fatigue you worry about is a result of repeated cycles of flexing. Like bending a strip of aluminum until it breaks. So, as long as any particular piece is used inside it's design limits, there is nothing to report fatigue wise. When you make repeated use of a piece far enough beyond it's design limit to generate distortion, the structure begins to break down. Mazda going to all stationary gears being hardened is an example. It is hard to believe that anyone would rev the piss out of a rotary, but appearently, so many owners did, that the factory finally caught on to it, and started hardening the gears.



Who could drive a rotary without seeing what the redline in 3rd feels like. And just like flying a plane, once there, who would want to leave. You become addicted to the endorphins. It feels so good to be pinned into the seat........................OOPS, I said more than I should have......



Anyway, the higher the stress, the shorter the life of any part.



Another example is lightened rotors. If you do that, you must lighten the counter weights as well. This gives you several benifits. One becomes obvious without instrumentation, and that is: a big decrease in rotational inertia. ( It winds up quicker, and pins you in the seat harder). Another is not quite as obvious, and that is it lowers the loading on the rotor bearings, the main bearings and the crank.



The crank gets bent into an "S" shape at high revs, and that misalignment causes the rear main bearing to drag along the front end a bit. Also the rotors are not running square in the housings and will drag the corners and hose the corner seals and some times the irons (or worse). If you look at the Mazda hop up instructions you see them opening up half of the rear main a bit to allow for this crank flex. I just scrape the front and rear of the bearing down to copper for about 1/8" and then open the whole thing a bit with some killed 600 silcone carbide paper in solvent. I have yet to loose a main bearing (since 1980) so i guess it works. Highest recorded revs so far has been close to 15,000 RPM. Now that did shine up the bearings and hosed the corner seals but we ran that motor the next day after a rebuild in the dirt at Road Atlanta. The REM thing works and is on the drawings for many high stress parts. The deep freeze stuff in liquid CO2 is on the drawings for many high stress parts.

Most often seen in torsionally stressed steel shafting. As in drag racing axels and helicopter parts, and similar.



But once again I have run on..........................



Lynn E. Hanover

You just put into a lot of words what Ive always thought on cryo treatment. I just thought Id throw that out there for arguments sake. The article I read was about a bone stock SCCA racing class(dont remember the car), but brake rotors had to be OEM, as well as pads, etc. The cryo treated stock rotors lasted considerably longer than the untreated stock rotors. The untreaded rotors were prone to cracking from the heat cycling after just a couple of races, while the treated ones went the better part of the season before needing to be replaced.

ive tried to quit, but um i keep falling off the wagon.....

pro7/ita/e prod are other classes like that. you have to use a stock brake rotor, and the oem ones lasted longer before exploding before the aftermarket ones, but they ran out of factory rotors, so now everyone has to change brake rotors every couple of races (or keep a good eye on em) so they dont explode.



it was a whole big thing in e prod, because the 1st gen rotor is also the wheel hub, so when it explodes its dangerous

Well, looks like I'll be upgrading. https://www.nopistons.com/forums/pub...#>/biggrin.png After rethinking what I intend to do with this motor it would be nice to have some extra insurance here and there. I'll have to do some more checking on the rene stat gears. Anyone know what Sollo II class they would putt me in if they'er even allowed? Maybe S5 or fd's would be better in my case.



NOTE: I am not a metalurgist, chemist, or physicist...ect. I simply enjoy reading/leaning technical/scientific things. So if I get something wrong, please correct me in a kind manner. I love to learn, and am willing to accept correction.



After reading about it some more, it appears that cryo treatment doesn't make a part more hard, but instead, helps to even the hardness, relieve stresses within the part mainly from the conversion of austentite to martensite, and assist in the precipitation of very fine carbides(mainly in carbide tool steels) throughout the crystline structure, thus increasing the wear/abrasion resistance of the part so treated. As I understeand, and as an example, It does increase the life of break rotors which I believe have no austenite in them to begin with.(pearlitic cast iron) So, the heating/deep cooling/heating process is doing more and is for more than just converting austentite to martensite.



Of couse, if a part has a significant amount of retained austentite, the part will grow from the coversion process as martensite is about 4% larger than austentite. Also, it is logical and and safe too asume that a part would need to be heat treated/tempered again after cryo treatment in order to stabilize/temper the newly converted martensite. I believe NASA is one of the main research/developers of the cryo process and has cryo treated components in use.



There are many people using crygenic processing on audio/electronic equipment, and they claim it does give them a noticable improvement in audio quality.



I do agree that some of the claims sound like baloney. But I can see how brass/metal musical instuments could also benefit if it truly does help to relieve internal stresses of the metal. That is why some of the best and well known wooden instument makers use/used aged wood. The longer a given piece of wood is aged the less internal stress it has, and thus better resonating properties. To me internal stresses are like static energy. They are constant forces fighting to find their own ballance while they are held in place. Instead of being happy together, some of residents in the crystaline latice are fighting. https://www.nopistons.com/forums/pub..._DIR#>/sad.png Any energy attempting to pass through a stress point will be impeded, distorted, reflected, or absorbed somewhat as it passes through. The weakest link in a chain always breaks, and so on and so forth...



Wether-or-not cryo treatment makes a big enough difference for us is another debate, and it apears most of you don't see any good enough reason to use it on anything other than brake rotors. I can say after doing more research, I can mostly agree. I would not do this on parts that need to have precise dimensions, unless I knew the exact percentage of retained austentite, or the part still needed to be set to the required dimensions i.e side seals. It seems better suited for use in production where it could be used before the final machining/finshing takes place.





I hope this made some kind of sense... I definitely think something contagious is in the air...



Oh no!... I've got E-NDLP (Electronically-transmited Neuro-Degeneration from Long Posts ) https://www.nopistons.com/forums/pub...IR#>/wacko.png https://www.nopistons.com/forums/pub...IR#>/wacko.png https://www.nopistons.com/forums/pub...IR#>/wacko.png





Thanks allot guys! https://www.nopistons.com/forums/pub...R#>/tongue.png

ive seen 1 engine failure that was the stat gears (driver downshifted into 3rd, but got 1st instead, engine ran but it clicked...)



and 1 engine failure that might have been the gears, but it could have been a bunch of other things too, we're not sure, every peice of the motor was broken....

Your first remark about converting austinite to martinsite at below zero degrees celcius is wrong. I'm not attacking you but that is just wrong.



NASA does not cryotreat anything. I may not work directly for NASA but my company is a customer of NASA as we do the canada arm for the space shuttle and for the international space station and we have every single NASA standard in our database. I reviewed all the NASA standards at one time since it was required when I started there, along with all Military specs, DOD, and ASTM specs and there is nothing written on cryotreating. Unless foriegn companies are excluded from certain NASA docs I believe we have the entire library. We design and manufacture based on NASA standards.



I also did a search using the SAE database for AMS docs pertaining to cryotreating. Nothing. If all these organizations do not have a standard or process for cryotreating that leads me to confirm my original conclusion that cryotreating is BS. I got a quick asnwer from my materials professor 1 year ago when I was taking a materials design course in my 4th year of engineering. He told me nothing happens below room temperature. I remember the lecture where I asked the question, his response was nothing happens below room temperature to the strength of a material even if you submerge the peice in liquid helium at 2.17 kelvins and raise the temperature back up.



I do know electrical properties change for certain ceramics as I had a 3rd year lab on super conductivity of

YBa2Cu3O7 and NbTi



Wood and metals are completely different materials. Please do not compare them. It is even worse than comparing apples to oranges. Wood is a composite of organic fibre which have closer correlation to carbon fibre and fibreglass, where the basic property of wood is carbon, carbon being an element. Metal is metal for sake of better words. The 1st year mateirals/engineering courses describe it as lattice structure of atoms with electronics freely moving in the lattice (or a pool of electrons).

I'm not 100% sure what alloy the gears are made from but it is probably some sort of Low Alloy steel which means it's heat treatable. If you wanted every last once of performance/strength/hardness I would find a reputable shop hopefully with ISO certs that can heat treat your gears.



Tell them you want to heat treat them to AMS-H-6875 (Heat Treatment of Steel Raw Materials).



Write: Heat treat to general requirements of AMS-H-6875 for 4130 alloys. Have them stick an additional peice of stock chromoloy. Tell them, verify that mechanical properties meet requirements in AMS-6350 with tensile test peice made from same stock and subject to same treatment as part. Test in accrodance to ASTM E8.



Then if you are super **** you can have the gears magnetic particle insepcted.



honestly how far do you want to go? I didn't realize rotary engines were meant to operate in space.

I forgot to put nitriding.



Tell the same shop you want the following.



Nitride as per general requirements of AMS-H-6875 for chromoloy alloys. Include additional peice of same stock and subject to same nitriding. Verify surface hardness of additional peice exceeds HRC 40.



Then stree relief gears as per AMS-H-6875 30°F below aging temperature. Tell them you want to have it reliefed at 50°F below aging temperature to account for variations temperature probe.



Then you need to inspect the part and insure that no single dimension has changed by more than 0.025 inches. If parts can not meet 0.025 inches variations after corrective machining then discard parts.



Don't forget to ask for certification of conformance and test results so you can analyze each and every single process.

I retired from my work in my beloved US Government as a technician in the acquisition area of The Defense Supply Center Columbus (Ohio). DOD, DLA, DSCC, SDP. One of the many schools Uncle Sugar sent me to was Specs and Standards school At Fort Lee Virginia. It turns out that most of those specs that so many people put so much faith in, are just acquisition tools written by morons like me. In fact the primary source for specs is the manufacturer that is making the piece we are already buying.



You don't get to see specs for cutting edge technologies because it is a blueprint for how a piece is made, or has enough intel to give most of a process or procdure away. So, the idea that It does not exist because you cannot find it on some list, is just foolish. You will not find much new stuff in your IHS library.



Government inspecters do use in-house specs to do in-process inspections inside a manufactueres facility, but may not posess the spec or remove it from the inspection area. The government may not even know what specs are used by any manufacturer for any particular part.



In most acquisitions the government is using the manufacturers in-house spec, which will be marked "Limited rights" and it is a violation of federal law to divulge specific data from that spec or drawing. The spec may also be elevated to NOFORN, which means no foreign access to this drawing or spec.



Where the "Rights" to data are purchased by the government, you will see, for example, Boeing drawings, in wide distribution. In those cases, as you would guess, the design is frozen to the last drawing date owned by the government. Where the government inspector has specific drawings to inspect to, they will inspect to the first level only unless there are contract clauses that call out exceptions to lower level specs.



The best acquistion situation is that where the buy is for a part number. Period. No in house inspection is called out in the contract, and inspection at destination for count and condition is all that the government is allowed to do. You will discover that NASA buys an enourmous amount of its stuff with no specs at all, just count and condition. In a large number of acquisitions, we had only the top drawing for use in identifying the piece. One or two outside dimentions and a color.



Our worst fear was a young engineer piling on specs as fast as he or she could look them up. You just shut off your source of supply by doing that. You may be aware that the government under pressure from our beloved congress and 60 minutes, has turned over to the SAE thousands of military specs and standards.



Without comment or consultation, the SAE set about (standardizing) hundreds of these items by removing this or that and inserting the "similar" SAE subspecs. This to make more money for themselves, because the spec in no longer free, but must be purchased from SAE.



So, for example in the area of stainless AN fittings, the type of stainless is changed and none of the manufacturers have ever made the parts from that material, and are not interested in starting to do it that way. Presto, you are out of stock on that item. We would have to call up the extinct version of the spec, and then write in the material exception to the new spec on each and every contract, covered by that spec.



We are just getting over the "just in time" contracting that the congress thought would work so well. The car companies have quit doing that in most cases. It requires more complete end items to be deployed to end up with the same number end items available. So, instead of a fitting on the shelf in Germany, you need an extra M1A1 Abrams tank.



What would have been cheaper? The fitting or the tank?



During WWII there were hundreds of quick built "Liberty" ships assembled all around the country for use in shipping war fighting supplies to Europe. Many were lost with all souls to submarines and surface ships.

This included those going inside the arctic circle taking aircraft the our friends the Russians. It was then thought that the Germans must have subs operating in those waters. This was not the case.



One day a Liberty ship made it into port with a foot wide split in the main deck from stem to stern.

The 60 below zero temps had made the steel alloy so weak that nearly any stress would fail it in a grand manor.



So there were no subs at all. The ships lost had split open below the water line, and sunk so fast that not even one SOS had gone out. A bucket of aluminum added to each batch of melted scrap iron cured the problem. So there is the begining of the idea for cryo treating of metals to gain this or that characteristic.



The Titanic disaster was another example of poor (nonexsistant) metalurgy.



I reacently toured a propeller manufacturing facility, where I did not notice any paper work attched to any "In-process" blades. The fellow leading the tour said they had their own quality system. I was expecting M-I-45208, or the similar Metric (French bullshit) spec everyone loves to advertise so much. So I doubled back and inspected each batch cart as it went through the plant. There was only one piece of paper for each cart. A few numbers, no names, machine numbers, blade serial numbers, no way to connect any blade to a manufacture date. A recent AD covering some of their products included some serial numbered hubs, some part numbers for that same hub, and a notation that some retailers may have applied part number of their own to those hubs. In othere words anyone with one of that style prop has to remove it and inspect the hub, to see if it is mismachined. They think they made 40 (or so) bad hubs, but they have no idea where they ended up.



Any known quality system in use here? I think not.



NASCAR uses cryo on high stess parts like axles. Fools wasting their time and money?



There is more on heaven and earth than you or I will ever know.



But again I run on.



Lynn E. Hanover

Ok so explain to me the process of cryotreating. At what temperature do we subject the parts to? For how long? What is the rate of change in temperature? Are there any peices that get tested to ensure a change in mechanical properties has occured and met your requirements? How does the rate of cooling affect surface hardness or tensile strength? How does it affect fatigue life? I can't find any information from that in any text book, spec, standard anywhere. Metals has been around a lot longer than the ability to make liquid nitrogen and hydrogen. If you are telling me that no one has invetigated or tried to drop a peice of steel into liquid hydrogen or nitrogen I would be stunned.



Specs and standards exist because someone took the time to do the R&D on the process and material to ensure that when others want to acheive teh same results they can be duplicated. It is fine to say, hey I want that part heat treated or stress relieved, because I want a certain surface hardness or fatigue life. But when the guy who operates the oven goes, so how long do I stick it in there for? What to do you. say, "stick it in for an hour?", what temp sir? "I don'tknow, what temperature do you use to roast a turkey?" Do you want me to air cool it or quench it in oil? All those things influence the final strength of the peice. That is what the spec is for. The spec tells you that hey, for given temp, for given rate of heat, for duration, and for rate of cool you get 175 ksi. If you skip a process you only get 150 ksi. That too me is important.



Revised drawings calling out a different material compared to the original design has no bearing specs and standards in this argument. A drawing is not a specification. A specification is instructions on how to conduct a process. A drawing outlines and details a part that is to be created.



You use these specs not in purchasing but in the design. If you designed a part and you need a certain strength and margin and you called for specific heat treatments to the material for your part then it better be done. I don't know what happens in the USA govt or military now, but in my current industry of aerospace... **** like that doesn't happen.



A specification/standard is used by the design engineer so that he/she can correctly select the correct material for their design. If you were in cutting edge design work you may be able to invent some new way of heat treating a material to get you an extra 5% of whatever, calling out for weird processes and such that isn't common to industry. An ASME/AMS/NASA spec has been written for engineers to follow.



It is up for teh company's QC to ensure that the part was manufactured according to design. the spec is not Quality control! It is a tool for selecting material. Just like how you look up the strength of different metals.



If I called for 7075 aluminum for a part, and the machinist used 6061 or 2023, it's not the spec's fault. It is the QC and the machinist not paying attension.

If I called for 7075 aluminum for a part, and the machinist used 6061 or 2023, it's not the spec's fault. It is the QC and the machinist not paying attension. The AMS spec tells me 7075-T6 has a yeild strength of 73 ksi where as 7075-O grade has a yeild strength of only 15 ksi. If my design parts need to carry a load that subjects it to a yeild strength of 50 ksi, I'm giong to call out the use of 7075-T6 and call out the proper spec for 7075 and tell the manufacturer that I want them to solution treat and precipatation harden the peice after rough machining per AMS-H-6088 to the T6 temper. Then I would have him remachine it for the final dimension. If the piece is cylic loaded I would then figure out if it will fail during it's operational time to fatigue, but won't if I stress relief it. Then i will call out stress relief and dye inspect

the liberty ships were one of the first completely welded ships as well i think, so they didnt have any inbuilt crack arresting features such as rivits and pannels, almost all steels have a brittle-ductile transition temperature which happens to be in the region of normal/cold environments. Im pretty sure you will find that austenite will transform to martensite below 0 degrees, the austenite-martensite is not a diffusion controled process like austenite-pearlite etc. The martensite start temperature is not always above zero either, have a look through some cooling curves (TTT diagrams)

When I was young, you were not permitted to throw away any kind of metal. It had to be turned in for the war effort. The need to collect and melt ironlike scrap into plate stock at a high rate, no doubt resulted in some unrecorded recipes of iron/steel alloys. The effect of cold stress was often fatal. Welding was hit or miss, (My mom was a welder) I was thirty before I laid down a bead she liked. She worked nights sanding parachute packing paddles (like paint stiring sticks).



The real alloys went to aircraft and submarines and everything else was made of crap. What does nichrome from a pile of toasters and a pile of car springs make when melted into plate stock? In some cases a German 88 would hit a vehicle, and it would fly apart as though a toy of some kind. It was a damn grim time.

Supposed armor plating shattering like glass when hit, in the cold. A real moral builder.



Sorry all of you young guys missed it.





Lynn E. Hanover

I feel like im right back at work.



Just to reinforce what Lyn is saying (as if he needs it) The prints follow a project from start to finish of that particular component. But to limit the chance of disclosing secret and propriatary info, a component, or unit, is built in several steps in different departments to keep a person or group of people from knowing or recording the exact specifics.



Cheers, Dont be surprised if you dont have all the detailed specifics reguarding processes used to fab or assemble everything. Its an elaborate system to keep knowledge in control.

Lynn, I believe we see the specification/spec idea that is being discussed for cryotreating/heat treating in this thread differently.



You are speaking of individual parts, such as Mil spec circular connector or mil spec wiring, or nuts and bolts. (Military specified parts), basically specifying that the part is the same if it has the same part number



I'm speaking of standards and specification for the production of parts, whether they be one off parts or parts that a GM engineer dreamed of for a suspension. A body of engineers, researchers, and academics researched the steps to follow to obtain a desired performance in the material. In this case we are speaking of heat treatments and cryo treatments. A recognized body be it SAE, AMSE, etc... has been able to repeat the researched process and has issued a way (standard) that others must follow in order to acheive the same result.



I'm not convinced that cryotreatments actually do anything. If you do say that I do not have access to all the documents and standards that the americans have classified or developed internally, then I would too assume Joe blow who runs cryo3000 or frozen rotors.com or whatever cryo treatment place doesn't either. I do not believe he/she has NATO security clearance and NASA clearence either. Then I must ask you how is he figuring out the steps necessary to subject parts to increase their performance? And how is he making claims as to how the parts have increased in performance? Did he drop the cryo treated part off his roof and say, the dent was smaller on the cryo peice than the one that was untreated?



How come I can't go down to the local metal supply shop to buy 4130-cryotreated grade, but I can buy 4130-heat treated grade? Liquid Nitrogen is not difficult to make? It would be super easy for the foundry to subject some of their peices to a liquid nitrogen dunk before shipping it out.



Unless I know exactly exactly what final

yeild stength

tensile strength

Rockwell hardness

change in dimension

Elongation at Break

Modulus of Elasticity

Bulk Modulus

Shear Modulus



I remain skeptical on claims of cryotreatments.

Yet, for years, people have preferred to use "seasoned" blocks, aka weathered, aka used, because pretty much all internal stresses will have normalized at that point.



Iron does weird things. It will move around long after you think you're done. Ford Y-blocks, fir instance, do some really odd things on the deck surfaces. Did Ford machine them with those weird rifts and valleys? No, the iron "settled" through use, and due to the idiosyncracies of the block casting, they all manage to settle into the same general shape.



BMW famously exploited this by using euphemized junkyard engine blocks for their F1 efforts. They held up better than new ones.

That process is called cold working. Plastic deformations cause the lattice to slip and forming a co-planar lattice which is stronger than a perfect lattice. Shot peening a peice of steel is a form of cold working. You can only cold work small objects. It is almost impossible to cold work something the size of an engine block with all it's intricate parts and pockets.

No it is not cold working, its closer to an aging process that you would use in a solution treatable aluminium. Cryo treatment does work for some applications and this is documented, namely transforming retained austenite to martensite in some tool steels, this transformation is not diffusion controlled so only the martensite start temp is important, however because of the difference in volume during the initial austenite to martensite transformation there will be stress fields in the material which will change the martensite start temperature. Incidentally most phase diagrams are for atmospheric pressure, the eutectic points can change depending on pressure. I agree with you on the break rotors and things like that, I have seen no info on that

This is quite a discussion.

I really appreciate all the feedback and time everyone has spent to discuss this.

Cheers!, thanks for the input. I'll see if I can look into those specs some more. Much of everyone's info seems to be going over my head right now. https://www.nopistons.com/forums/pub...IR#>/blush.png (I'll reread when i'm not as tired)

In some of your posts you referred to cryo treatment as dunking a part into the liquid gas. None of the companies I've researched describe their process as dunking parts into a liquid gas; rather, most of them claim to have some process of gradually lowering the temperature to the target temp, holding the piece at the target temp for a period of time, and then gradually bring the piece back to room temp. I think every one claimed the process does convert retained austenite to martensite.



Yes, most of the information I was able to find was from the various cryo companies, so you have to sift through their claims and see if they are just sales hype or real information. Just because there are so many cryo treaters out there does not mean it is a proven process, and the great lack of information does make it suspicious. Are these companies just hoping the customers will believe it made a difference and continue to do business with them? After reading testimonials(not posted by the cryo company) of people who found an increase of life span from (a) part(s) they had cryo treated, I have to believe(for now) that there is some validity to cryo treating.



When I have more time I might post some links that I found with some more in-depth info. I'd rather not be a repeater, and I don't think many people appreciate it either. Much of what I found is there for anyone to see via google. I wish I had more hands-on experience, but that's the consequence of being young.



About the wood/metal comparison...

I only meant to compare how I could buy one of a cryo company's claims of how metal instruments could be improved by relieving more of their internal stress, as I am familiar with the affects of the built-in stresses of wood and how it can greatly reduce the quality of sound when used in an instrument. I wasn't thinking about wood/metal per se; just the path of sound waves passing through or resonating from something with more or less internal stress.

I sometimes oddly, wrongly, or oddly and wrongly word things in an attempt to relay my ideas, or run-on with residual thoughts remotely related to the subject of my idea, as an outcome, I may be taken to say, or even truly say something that is odd, wrong, or odd and wrong. I apologize.





Well, I need to go get some rest before it gets too late(already is. lol). I'll be spending the whole day, from sun up to who knows when, helping pour and finish 65 cubic yards of wonderful crystalline matrix forming concrete... https://www.nopistons.com/forums/pub...R#>/tongue.png

In conventional heat threatments If you convert austenite to martinsite you get dimensional changes (ie warping). Now with brake rotors you can remove enough material to make it run true again. If cryo treatments do in fact change austinite to martinsite (no proof as yet, as I can not find anything that is documented from any one or any organization with creditability) how are you going to machine the teeth of the stationary gear so that it is within mazda's tolerance again?



When I refer to cryotreatments i use the term "dunk" since you need to take a part to the temperature of liquid nitrogen and ensure it is homegenous throughout the peice. Even if you rig up a fancy chamber and start to feed in liquid nitrogen to control the rate of cool you will need to eventually fully submerge the peice to ensure the entire peice has reached liquid nitrogen's temperature.



So what temperatures do they do cryotreatments? Do they have the dwell time at liquid nitrogen temps or at liquid helium's temperature?



Newguy707: For the price of cryotreating process, why don't you just buy racing beat hardened gears? or FD gears? or rx8 gears? They aren't that expensive, and are already proven to work.

;j

Skeptical should be the minimum.



When a factoid shows up that seems to violate common sense, just smile and listen. I thought I had been the most lucky man alive because of all of the advances that had been made while I was here. I was wrong.



Improved communications and the home computer have bent the learning curve upwards at a steep angle.



The cryo thing is just taking off. Big companies don't buy this equipment if there is nothing to it. There are thousands of specs and standards that we can never see, because the intel people can tell what you are working on by obtaining just a few of them.



The rustbelt spec holders have none of them because the security stamp is higher than any document control spec compliance they could meet. Far more than I have seen for sensitive and NOFORN. If you were involved in a project you can only get a spec through supervision and a document officer who will determin if you need to see that document. You would not say a word about any spec or standard that you have seen.



When you sit in on a meeting where you have a little scrap of the pony show, listen to all of it. I often was able to piece togther a much bigger part of the picture than I was supposed to know about.



There are now specifications for the cooking up of Nanotubes and Buckey Balls. Less than 10 years after being discovered, you can buy kilogram quantities of this stuff from a number of manufactures. Those documents that AMSE or SAE will use to write anything they will, must come from the industry that has the knowledge about it. The industry is not in the mood to do any such thing for competition reasons. So the rust belt spec holders may not see anything for some time after the fact. If the government needs to have "In process" inspection of the newer stuff, then only those documents provided by the manufacturer will be available. Unless the government buys the data, the government cannot remove any data from the inspection area.



The cryo stuff may not perform as advertised by those touting it for their own gain.



The number of really smart people and corperations useing it would seem to indicate otherwise.



The profound effect that seemingly modest cold has on some alloys, leads me to think that a more permanent change could be had at much deeper temps, held for a week or so. The room temperature idea is

just a point on a chart to metals. Metals continue to change shape and suffer measurable changes all along the temp scale.



Twenty five years ago if I told you that I had developed a metal with a shape memory, that could be triggered by the temperature change generated by the radiant heat from your hand, what would you say?



There are no specs for it? It cannot be so?



Now you can buy it. You can make a motor that turns a generator that runs because one half of a motor is exposed to the sun while half is shaded. Direct conversion of sunlight to work. A statment so outlandish then, that nobody would believe it. And here we are now and it is common as dirt.



A whole new (high tech) industry is being developed around soot from smoke stacks. Petroleum engineers have been studying soot since just after dirt was discovered. How did all of those people miss carbon 60 and carbon70? (Soot is used in rubber products like tires to add strength and wear resistance)



The first peer review the boys got back after they published on the carbon 60/70 find was from Bell Labs.



Usually a few pages that refute or varify findings and suggestions for use. The Bell Labs engineers thought of a few uses for the strands with the strength of a diamond. Their review submission was as thick as a NYC phone directory. (And they did not send the really good stuff), if you could reduce the weight of the 25 ton wing spar in a 747 to 7 tons and reduce the cost of manufacture by 50%, would there be any advantage in that?



A few rears back, a teenager form a town just north of Columbus was making industrial diamonds in his garage. His process was so simple and so inexpensive as to be laughable. GE bought him out. How did all of the thousands of engineers around the world who worked on this daily not see this process?



Never say never.





Lynn E. Hanover

one thing that science is not good at is that we think we know everything at any one given point, and is usually proven wrong. remember the earth was flat? we didnt orbit the sun, the sun orbited the earth? tobacco was thought to "clear the pores and release the vapors" in the 1600's, we thought dinosaurs moved slowly, betamax was a good idea, leg warmers.

I thought it still does!



anyhow, what good is cryotreating when I can't even determine the final increase in strength. I'm not talking abuot, hey lets just throw some brake rotors or stat gears in and make myself feel better that I did it instead of not doing it.



I'm talking about more general use of cryotreating, such as when someone has to design a new part from scratch. How can you design the part calling for processes that you don't even know the increase in performance. Atleast with heat treatments and traditional methods I know exactly what the recovered strength / increase in performance is.



I for one would not use cryotreatments, even if you did believe it increased the performance of the treated peice, how do you know by how much, how do you know piece A is the same as peice B that was reated the next day? You need to know the performance values of tensile strength, yeild strength, etc etc... in order to create you part with the necessary dimensions and calculated margin so that you can use cryotreatments to an advantage. If you said ya, we want you to design a new shaft for a chain sproket application, and we want you to use cryotreatments. The fact I can not find any hard evidence on the sucess or increase in performance after cryotreatments means I will design the shaft in a way that I assume cryotreatments do little to change anything, and make sure I have double or tripple the margin in the calcs just in case cryotreatments have negetive impacts on the metal.



Why would you use an unproven, undocumented, process with unknown results with the only thing you know is that on internet websites, discussion forums, and word of mouth telling you that "ya, my brake rotors or my crank shaft was treated, it's awesome, it's so much stronger". It's like buying live for ever magic water. Or listening to get rich quick schemes advertised in infomericals.



So how much stronger? Why can I not get a quantitative value for the material properties for anyone I ask, or how ever much research I do?

yeah i agree with you, i'm not having any failures or unusual wear anyways

im deffinitly not an advocate of cryo treatments, but it has been proven and it is documented that it does transform 'retained austenite' to martensite. There is generally not a large volume of retained austenite so there is minimal dimensional changes, so it can sometimes be used to increase the dimensional stability of a component. Under high applied stress retained austenite can from 'burst martensite' which can be more brittle than plate or lathe martensite. So cryo treatment may not increase strength as such but could increase fracture toughness, which is potentially a better design parameter than yeild strength. The amount of retained austenite is entirely dependent on the alloy and previous heat treatments.

The one feature I read about was extended life in shafting with splined ends where fatigue failures were propogating from the spline roots. Same for torsion bars.



I would get a list from one of the companies that does this stuff of their customers. The talk to engineers at those companies about what they expect from the process. See what testing they did. They may even provide you their test documentation and even samples. And if they have inhouse specs they may provide them. I used to be able to get samples of damn near anything, from anyone.



People are proud of their work and love to show of examples, provided your company is not a competitor.

People sent more **** to the government than Carter has liver pills. We had stacks of racing clutches and discs, when we were looking for a better clutch setup for the Chevy Blazer. When we got done testing them,

we gave them away. All too big for anything I needed.



See if one of the cryo companies has samples of bar stock, or whatever, that have been, and have not been cryo treated, for you to test.



Lynn E. Hanover