cryo temp

warrior24

warrior24

Joined
May 3, 2006
Messages
673
I was thinking the other day if you turned a can of compressed air upside down on a blade would it get cold enough to cryo-temper it, or does it have to be done for a long time, maybe dry ice would work. what do you guys think?
 
warrior24 said:
I was thinking the other day if you turned a can of compressed air upside down on a blade would it get cold enough to cryo-temper it, or does it have to be done for a long time, maybe dry ice would work. what do you guys think?
Click to expand...

Well, I had the same idea and I'm going to try it but I think the true cryo process involves lower temps. The co2 Dry ice will be about -110 F and if I remember from some reading somewhere they are going down to -200F + for cryo tempering. There has to be at least some benefit from the dry ice cryo tempering and you do need to do it for a period of time give the metal a chance to transform, just like soaking it on the heat up for heat treating.
Just my opinion, JD
 
It doesn't last lone enough, and isn't cold enough. Even the dry Ice method is borderline. -110 is low enough to get some benefit, but you have to use alcohol or another media with it. This bring it up to apx. -56 to -75 if memory serves. Mike
 
Dry ice is about -100 F, liquid nitrogen is about -300 F. The temperature has to be uniform and held for hours.
 
I think there may have been some misunderstanding about the temp of the dry ice / acetone mix. The poster in that thread was using equal portions of each to approximate a temperature in the middle.

If you keep adding dry ice to the acetone until it stops bubbling - and then some more, the temperature will be at or very near the -109 of the dry ice. It's plenty cold enough for good cryo. The poster was right though, that it doesn't last long long. 1 batch of blades overnight is probably all you are going to get out of a medium size cooler of dry ice pellets. Liquid nitrogen in a dewar just lasts longer - no other real avantage.

Rob!
 
You must log in or register to reply here.
Back
Top