Thread: Liq. N2...so what if I.....?

Here is a question for you guys!

What, if any effect would placing an old (late1800's) razor in liquid nitrogen do? Would it help the hardness, would I risk cracking the blade, just make the blade VERY cold, etc...?

Also, if I were to try this would you recommend a slow progression to the temperature differences and then a slow progression out?
(e.g. 4 C, -20 C, -80 C, -140 C, Lq N2, -140 C, -80 C, -20 C, 4 C, Rt)

I'm not too familiar with cryo-tempering of metal and am thinking of 'tinkering' with a blade I have been putting 'through the ringer'......

C utz

Originally Posted by C utz

Here is a question for you guys!

What, if any effect would placing an old (late1800's) razor in liquid nitrogen do? Would it help the hardness, would I risk cracking the blade, just make the blade VERY cold, etc...?

Also, if I were to try this would you recommend a slow progression to the temperature differences and then a slow progression out?
(e.g. 4 C, -20 C, -80 C, -140 C, Lq N2, -140 C, -80 C, -20 C, 4 C, Rt)

I'm not too familiar with cryo-tempering of metal and am thinking of 'tinkering' with a blade I have been putting 'through the ringer'......

C utz

How come I never have cool stuff like liquid nitorgen just layin around??? I have to reevaluate my stockpile

Liquid nitrogen improves gun barrels, which have already been forged/heat treated, so I see no reason it wouldn't improve a razor. I think the effect would be less, however, than if it had happened at the time of heat treat. Paul Bos, who does the ht on my knives, cryogenically treats them immediately after quenching, to help with the tranformation of retained austenite. The resulting blade displays finer grain structure, greater flexibility, improved edge holding, and ease of sharpening. Still, if it doesn't crack the blade, you should notice improvement. One thing, though, is that it would be better to gradually lower the temperature than to just quickly submerge the blade, to reduce the stresses on the steel.

Joes forgetting all the other cool stuff liquid nitrogen is good for, for instance...if you dip a banana into liquid nitrogen...out comes a hammer Its also great for quickly freezing chocolate bars as well

Originally Posted by JLStorm

Joes forgetting all the other cool stuff liquid nitrogen is good for, for instance...if you dip a banana into liquid nitrogen...out comes a hammer Its also great for quickly freezing chocolate bars as well

Oh yeah, Josh...supposedly, liquid nitrogen will make your pantyhose last longer, too, with fewer runs.

Originally Posted by Joe Chandler

Oh yeah, Josh...supposedly, liquid nitrogen will make your pantyhose last longer, too, with fewer runs.

I'll have to try that lol Ya think I can justify the purchase to my wife if I tell her about the panyhose thing??

It should be good for wart removal as well

Originally Posted by Joe Chandler

Liquid nitrogen improves gun barrels, which have already been forged/heat treated, so I see no reason it wouldn't improve a razor. I think the effect would be less, however, than if it had happened at the time of heat treat. Paul Bos, who does the ht on my knives, cryogenically treats them immediately after quenching, to help with the tranformation of retained austenite. The resulting blade displays finer grain structure, greater flexibility, improved edge holding, and ease of sharpening. Still, if it doesn't crack the blade, you should notice improvement. One thing, though, is that it would be better to gradually lower the temperature than to just quickly submerge the blade, to reduce the stresses on the steel.

Well, I know what side project I'll be trying this weekend
(and it's not the pantyhose thing....maybe next weekend! )

C utz

I doubt it would have any real disasterous effect, but I would use a cheaper blade, just in case.

BTW, LiNi is too fun to play with too. One day, one of my profs brought in some and used it to demonstrate some of the properties of superconductors to us. If you cool certain ceramic materials to LiNi temperatures, they become superconductive; and, as a superconductor, have very neat electromagnetic properties. The exact type of properties that let you float a magnet above one of these superconductive discs, and it just stays there, floating in mid air, with no power. One of the coolest things I've seen.

It was also funny seening him precariously pour the stuff from a 20 or so litre jug into a 1 inch deep styrofoam coffee cup. He pretends to accidentally spill a whole bunch with a dozen people sitting around the table. Never before have I seen anyone jump back so fast. Too funny

Whoa there folks.

LN is fun to play with. Okay I'll give everyone that.

LN, despite clever advertising, has not been shown to improve plain carbon steels that were originally heat treated correctly.

LN, can improve the conversion of retained austenite in high alloy steels, meaning those that contain chrome, moly, etc. Stainless steels and gun barrel alloys fall into this category.

There is a lot of hype and flat out conflict of interest out there. The folks hyping the research are the very same people interested in selling you the equipment to do this with. That makes me very cautious.

I have a great respect for Paul Bos. He's heat treated some of my blades in the past. But about all he works with is high alloy steels and his LN regimen is exactly as it should be.

Here's a link to the fellow who should know something about the subject. He describes using cold treatment on steel in one of the middle chapters. What is notably absent is any discussion of using cold treatment on plain carbon steel.

http://mse.iastate.edu/fileadmin/www...hoeven/7-5.pdf

If you put a blade into a LN system, remember that the blade now has untempered martensite in it and MUST be tempered again after such treatments. Otherwise you have brittle martensite. As if razors aren't brittle enough already.

Just want to slow down the stagecoach before somebody has to pull too hard on the reins...