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Location:
Eastern Melbourne
Registered:
January 2005
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cryogenic treatments for engines.
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Sat, 13 August 2005 09:36
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I read in an old ZOOM magazine about cryogenics for engines.
it seemed to make alot of sense, its kindof like nitriding but goes the whole way through the part instead of only a few millimeters.
they claimed that it made a block upto 300% stronger!
has anyone had experience with cryogenics?
id like to hear what people think about it.
i'm considering applying it to my full-house 4K build.
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I supported Toymods
Location:
Epping, Sydney
Registered:
May 2002
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Re: cryogenic treatments for engines.
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Sat, 13 August 2005 09:49
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the block is very rarely the thing that lets go when an engine shits itself. or if it is, it's usually the result of a rod going thru it 
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Location:
Eastern Melbourne
Registered:
January 2005
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Re: cryogenic treatments for engines.
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Sat, 13 August 2005 09:54
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you can get rods done aswell, i wonder hoe true the claim of 300% is?
if it is, i wont use anything after market, all stock cryo-treated 4k parts.
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Location:
Melbourne
Registered:
May 2004
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Re: cryogenic treatments for engines.
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Sat, 13 August 2005 09:59
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I was told that cryoing stuff like your crank acutally bends it all out of wack and then a straighten is required and more grinding and machining in general.
I am nitriding the crank that is going into my 4ac twin cam turbo.
Jeremy
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: cryogenic treatments for engines.
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Sat, 13 August 2005 11:12
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| frontspinner wrote on Sat, 13 August 2005 19:36 |
it seemed to make alot of sense, its kindof like nitriding but goes the whole way through the part instead of only a few millimeters.
they claimed that it made a block upto 300% stronger!
has anyone had experience with cryogenics?
id like to hear what people think about it.
i'm considering applying it to my full-house 4K build.
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i hate to be the one to say it but you/they have absolutely no idea.
nitriding. part is heated to maybe 6-700 deg and nitrogen adsorbs, and then absorbs into the metal, either forming nitrides (hard compunds), or strengthening by interstitial mechanisms. nitriding give higher hardness WHERE IT IS NEEDED. at the surface...
that said, nitriding a crank is kinda a waste of time because you should never let a crank touch the bearings anyway  if it does, the engine id ucked regardls of whether the crank is nitrided or not..
cryogenics. part is cooled down to HELP TRANSFORM RETAINED AUSTENITE into ferrite and cementite.. possibly as pearlite. because austenite is metastable, this may ocur, but the kinetics are very slow because diffusion at low temps is negligible (usually i consider difusion below 600deg negligible  ) it may chnge the austenite to martensite as that is a difusionless transformation... either way, the surface becoms a little bit harder, thus wear resistance, and the part supposedly has a bit better thermal stability.
it ay help "settle" a block that is relatively new and hasn't seen too many thermal cycles.. but to apply this to a 4K build is just pissing up a wall... unless you are planning something radical with the valvetrain, the rest is a waste of time.. basically...
as for cryogenics and alloy... well.. some ppl say they get results... they are usually either the companies doing it.. or ppl that have paid a lot of money to have it one... im not saying it doesn' do anything.. just for 99.999% of people, it's not really worth considering....
except for gearsets.
Cya, Stewart
edit, cbf fixing speeling.. to busy eating tofu
[Updated on: Sat, 13 August 2005 12:03]
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: cryogenic treatments for engines.
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Sat, 13 August 2005 11:24
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| Rallystanza wrote on Sat, 13 August 2005 19:59 |
I was told that cryoing stuff like your crank acutally bends it all out of wack and then a straighten is required and more grinding and machining in general.
Jeremy
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that is quite possible depending on how the crank was made in the first place...
anyway i'm curious to hear what a "full-house 4K" entails and what the aims are 
turbo or 10,000rpm?
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Location:
Eastern Melbourne
Registered:
January 2005
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Re: cryogenic treatments for engines.
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Sun, 14 August 2005 00:53
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yeah i thought that cryo article sounded too good to be true, ZOOM must have got some kind of special deal to let a cryo company write an article...
when i say full-house 4k build, i mean i aim to get about 100hp,
not full-house (aka,fully sick) by some people's standards...
but what power output does a standard 4k put out from the factory? 50 something hp? so if i manage to get 100hp thats around double the factory output, so in my books, a 100% power increase in an engine design from over 30 years ago is a Fully sick effort.
ps. is there such thing as a 4k that can handle 10,000 rpm?
i mean anything is possible with the right ammount of money, but has it actually been done?
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Location:
Brisbane
Registered:
July 2005
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Re: cryogenic treatments for engines.
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Sun, 14 August 2005 03:43
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Oldcorollas,
I'm curious about the "except for gearsets" comment.
Cryo treatment is quite popular on high end steel dirtbike sprockets. Reading through the info you posted it would seem that nitriding would be the better option for this application.
Surface hardness is measured in Rockwell? I think.
Any idea on how much each method would increase this figure.
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: cryogenic treatments for engines.
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Sun, 14 August 2005 03:57
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| Lukass wrote on Sun, 14 August 2005 13:43 |
Oldcorollas,
I'm curious about the "except for gearsets" comment.
Cryo treatment is quite popular on high end steel dirtbike sprockets. Reading through the info you posted it would seem that nitriding would be the better option for this application.
Surface hardness is measured in Rockwell? I think.
Any idea on how much each method would increase this figure.
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well... aiui, cryo is used predominantly for parts which have had heat treatments, like quench/temper etc (now that i remember more correctly...) because the point of the quench is to change the austenite (metastable high temp phase) into martensite/bainite etc, which is harder....and is a diffusionless transformation pretty much.. which is why the lower temp works.. higher driving force for a solid state transformation.
car gearbox/diff parts have surface hardening treatments, and cryo DOES work for them, giving a harder more wear resistant surface layer.
if the dirtbike sprockets have a surface hardening technique involving quenching etc, then it is very likely that this is a good thing.
surface hardness is measured by a number of different methods.. many in fact.. using either a steel ball of diamond indenter.. rockwell, brinell, vickers.. micro and nano indentation.. rockwell is popular in the US which is why you hear it often (damn loud yankees )
nitriding is also another method that can be used but....
well, it comes down to design.. if the alloy used for the part suits a temperature only hardening technique, it will be cheaper.
if the alloy has the correct composition to be able to use nitrogen hardening, then it may work out better, you can also use carbon hardening, carburising, which just increases the surface carbon content of the steel, making for better quenching treatments
my guess is that the metallurgy for the sprockets and their surface hardening techiques are pretty well established, and cryo was the next step.. as opposed to reinventing the sprocket...
as for which is harder/more wear resistant.. it totally depends on the base alloy... and i don't really know off the top of my head...
Cya, Stewart
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I supported Toymods
Location:
Epping, Sydney
Registered:
May 2002
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Re: cryogenic treatments for engines.
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Sun, 14 August 2005 04:29
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and the next question - would you be able to do a "test" of this technique when you get back to oz, if a certain person were willing and able to provide new gbox parts?
(when are you coming back anyway, bludger)
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: cryogenic treatments for engines.
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Sun, 14 August 2005 04:39
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| draven wrote on Sun, 14 August 2005 14:29 |
and the next question - would you be able to do a "test" of this technique when you get back to oz, if a certain person were willing and able to provide new gbox parts?
(when are you coming back anyway, bludger)
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well... it would be better to use a commercial cryo treater, because it takes a bloody long time and the cooling/heating rates are critical to reduce part deformation (i think)
as for checking the retained austenite percentage by metallography, that should be reasonably easy.. the amount is maybe 5% (as a guess) and afterwards maybe a few %.. i really should look it up )
i could cut things up... but i cannot do the treatments.. the techs in the EMunit would kill me for nicking all their nitrogen
umm.. what year is it now? mid '07 at the earliest.. maybe '08.... i'll just have to keep collecting parts until then
i wish i was bludging.. sunday and i'm still at uni.. and it's summer holidays 
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Location:
Brisbane
Registered:
July 2005
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Re: cryogenic treatments for engines.
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Sun, 14 August 2005 04:47
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Thanks for the great answer.
In this case they are actually steel sprockets, according to the spiel "the highest carbon steel available". There is a decent weight penalty with them but they are damn near indestructible. I was just curious why they would use cryo when nitriding is specifically aimed at surface hardening. I see now that there are many other factors to consider before the final treatment comes into it.
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: cryogenic treatments for engines.
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Sun, 14 August 2005 04:58
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highest carbon content steel... hmmm
at some point of increasing carbon content, the definition of an iron based material changes from steel to cast iron....
for a high carbon steel, the carbon is already there, so you may as well put it to work.. i can't remember if carbon or nitrogen is more effective, but i suspect that a surface hardening heat treatment would be a shiteload easir for them
weight penalty?? what are they usually made from??
oh and if searching for cryogenics articles/pages, you really have to be careful.. a lot of them are pure bullshit... even a few journal articles that have been puclished (but funded by companies) are crap...
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