Cryo Treatment?
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No help on auto parts but I did have a barreled rifle action treated by these guys -
http://www.300below.com/site/home.html
They were quick and the price was reasonable. Who knows if the gun shoots any better or will last any longer because of the treatment though...
http://www.300below.com/site/home.html
They were quick and the price was reasonable. Who knows if the gun shoots any better or will last any longer because of the treatment though...
Isn't that what Ted Williams had done to himself??
Dunno if this helps but they offer this kind of treatment for brass instruments. I was thinking about having it done to my trombone. It's supposed to release the stresses of the metal to make it uniform so that it will produce a better sound. Kinda different for cars...
Kestas
Staff member
Cryogenic treatment is an acceptable form of improving heat treated (quench and tempered) steel. This treatment has been studied and is accepted in the proferrional engineering community. Beyond that it become more like snake oil treatment.... hence it sometimes gets a bad name because some treaters expand this service beyond its accepted scope.
Let me see if I can keep this simple. What this treatment accomplishes is that it converts the soft retained austenite in hardened steel to hard martensite, gaining more available hardness and strength to a part, and rendering the part more stable by heading off any future retained austenite conversion that often happens during use. Depending on the alloy, process, and heat treatment, retained austenite levels can sometimes reach up to 50% in some parts.
Proper cryotreatment involves incorporating this step some time before tempering of a quenched part. You can't just willy-nilly take a heat-treated part in the finished condition and cryotreat it. The newly formed martensite will be brittle and provide crack initiation sites under load or Hertzian stresses.
Cryotreatment is best suited for small hardened steel parts that are expensive to manufacture such as machine cutting tools. It's been shown to improve tool life dramatically... 300% gain is not unusual. Large parts consume more liquid nitrogen and aren't as economically viable to cryotreat.
For non-heat-treated steel, cryotreatment may relieve some stresses - I'm not sure - but stress relief is better accomplished by heating a part - not chilling it.
Let me see if I can keep this simple. What this treatment accomplishes is that it converts the soft retained austenite in hardened steel to hard martensite, gaining more available hardness and strength to a part, and rendering the part more stable by heading off any future retained austenite conversion that often happens during use. Depending on the alloy, process, and heat treatment, retained austenite levels can sometimes reach up to 50% in some parts.
Proper cryotreatment involves incorporating this step some time before tempering of a quenched part. You can't just willy-nilly take a heat-treated part in the finished condition and cryotreat it. The newly formed martensite will be brittle and provide crack initiation sites under load or Hertzian stresses.
Cryotreatment is best suited for small hardened steel parts that are expensive to manufacture such as machine cutting tools. It's been shown to improve tool life dramatically... 300% gain is not unusual. Large parts consume more liquid nitrogen and aren't as economically viable to cryotreat.
For non-heat-treated steel, cryotreatment may relieve some stresses - I'm not sure - but stress relief is better accomplished by heating a part - not chilling it.
Thread on 24HourCampFire forum about cryogenics
Mule Deer is the gun writer John Barsness.
Mule Deer is the gun writer John Barsness.
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The rhetoric, as I understood it, was that tensile strength was not increased with cryo treatment. The stress relief just made it more uniform and therefore less "defective".
I bought a throw away razor allegedly cryo treated. It lasted over 6 months. The really fine edge lasted about 3 or 4 days ...and that's where it stayed. No nicks or pulls. I clogged it with a two or three day growth and pitched it.
When CNET had a cable program they featured one such shop. They used a room and did many pieces at once. They apparently "deep cycle" everything very slowly.
They described the action as if you had a large room with a bunch of random small groups ..forcing them to condense in the center ..and they allow them all to take one step outward at a time until they were evenly distributed.
I haven't used the service (other than to buy a few throw away razors). It may be snake oil ..but boy ..they hit a main vien of it.
Obviously I don't have a clue about metalurgy.
I bought a throw away razor allegedly cryo treated. It lasted over 6 months. The really fine edge lasted about 3 or 4 days ...and that's where it stayed. No nicks or pulls. I clogged it with a two or three day growth and pitched it.
When CNET had a cable program they featured one such shop. They used a room and did many pieces at once. They apparently "deep cycle" everything very slowly.
They described the action as if you had a large room with a bunch of random small groups ..forcing them to condense in the center ..and they allow them all to take one step outward at a time until they were evenly distributed.
I haven't used the service (other than to buy a few throw away razors). It may be snake oil ..but boy ..they hit a main vien of it.
Obviously I don't have a clue about metalurgy.
Kestas
Staff member
Rugerman, I read the thread on cryotreating gun barrels and it is such a waste of money. Like I said, it needs to be done during the heat treating of the steel, before tempering, and BEFORE machining. The way they're doing it now, they'll end up with harder, but potentially warped barrels.
Kestas,
thanks for that.
All I could think was that cooling metal so far could "stress relieve" by creating microcracks that relieved stresses, but at a possible detoriation of overall strength.
Your explaination helped me greatly.
Before heat treatment now does make sense to me.
Thanks all for your input.
thanks for that.
All I could think was that cooling metal so far could "stress relieve" by creating microcracks that relieved stresses, but at a possible detoriation of overall strength.
Your explaination helped me greatly.
Before heat treatment now does make sense to me.
Thanks all for your input.
Interesting that opinions vary so widely on this. I admit that it certainly sounds bogus. However, a fair number of engine builders treat blocks and cylinder heads with it, and swear by their results. Just have to test it myself, I guess.
Would steel produced in a zero-gravity enviroment be better than cryo-steel, and of course plain steel made on earth. I've heard that if they were to create steel in space, it'd be a lot stonger.
Kestas
Staff member
The only metal I know that's been studied in space is cast iron. Solidification under microgravity conditions produced graphite in the microstructure that had directionality. This made for material that had thermal conductivity properties that varied depending on direction of transfer.
Making materials in space would be different, not necessarily better. I'm not sure what differences would make steel stronger. Most commercial steel is still rolled into mill product and rarely used in cast form.
There's nothing about heat treated steel that is affected by gravity. Microgravity or earth - the principles of hardening are unaffected. Microgravity can only affect casting processes.
I'm amazed at all the misconceptions people have about metallurgy...... "creating microcracks that relieved stresses" (not that I want to embarass Shannow)..... when some hot rod magazines try to talk metallurgy everything seems to boil down to "rearranging the atoms" to achieve higher strengths. The last time I bought brake line tubing the kid at the counter told me to "warm the tubing in my hands so it will be easier to bend." I don't like to embarass people so I had to hold my laughter until I left the store.
Making materials in space would be different, not necessarily better. I'm not sure what differences would make steel stronger. Most commercial steel is still rolled into mill product and rarely used in cast form.
There's nothing about heat treated steel that is affected by gravity. Microgravity or earth - the principles of hardening are unaffected. Microgravity can only affect casting processes.
I'm amazed at all the misconceptions people have about metallurgy...... "creating microcracks that relieved stresses" (not that I want to embarass Shannow)..... when some hot rod magazines try to talk metallurgy everything seems to boil down to "rearranging the atoms" to achieve higher strengths. The last time I bought brake line tubing the kid at the counter told me to "warm the tubing in my hands so it will be easier to bend." I don't like to embarass people so I had to hold my laughter until I left the store.
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Well, misconceptions or not, they're not irrational concepts. Many who have worked with metals in the field (not casting, rolling) have (probably) seen metals crack under applied heat. How much of a stretch is it to assume that sending it the other way may do the same
I mean it's not like you pulled it out of your arse.
(visions of angry arab who gets flat tire, "Da/n jews!!")
Kestas
Staff member
Yeah... I know... you're right. This was just a personal observation from someone who has spent decades working with metal on a macro amd micro scale. After a while, you really get a 'feel' for what goes on on a micro scale and know what's myth and what's real.
NO, that's what Ted Williams' son had done with Ted.
Kestas
Staff member
Here's the recipe I would use for incorporating cryotreatment with hardening steel:
- rough machine
- austenitize
- quench
- cryotreat, without too much delay after quenching such as within an hour
- temper, again without too much delay
- final machine (grinding and honing)
Steel can be further stabilized by reducing the retained austenite with a double (or even triple) temper, as is often done on tool steels. It's basically just tempering again after the part has cooled after the first temper. In those cases it is desirable to cryotreat after the first temper.
With this said, realize that for some applications the presence of retained austenite is actually beneficial in the hardened steel structure as it gives more ductility and raises fatigue resistance in a part. Gear teeth is one such application.
- rough machine
- austenitize
- quench
- cryotreat, without too much delay after quenching such as within an hour
- temper, again without too much delay
- final machine (grinding and honing)
Steel can be further stabilized by reducing the retained austenite with a double (or even triple) temper, as is often done on tool steels. It's basically just tempering again after the part has cooled after the first temper. In those cases it is desirable to cryotreat after the first temper.
With this said, realize that for some applications the presence of retained austenite is actually beneficial in the hardened steel structure as it gives more ductility and raises fatigue resistance in a part. Gear teeth is one such application.
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