why the hatred for S.S. blades

[mete]

The Ms for D2 is about 430 F, no data on the MF. RA - hardened and oil quenched at 1800 F - 20 %. At 1875 F, 35 %.Cryo is defifnitely helpful.

 

[Greg Obach]

Hi

i did some searching... and this google book came up..
http://books.google.ca/books?id=_a9...&oi=book_result&ct=result&resnum=10#PPA341,M1

on pg 341... it does show that two cryo/temper cycles to 203k reduce the RA from 4.3 to 3.3 in the 2nd cycle..

so from this article ...there is an affect.... ( it would be nice to see from multiple sources since theres already enough bizarre claims to do with cryo and unobservable phoenomena )

this site say's :

Mf (a temperature at which the transformation of martensite is essentially complete) lies between -80ºC and -110ºC. At the temperature down to -100ºC, retained austenite in the as-quenched microstructure transforms to martensite, resulting in an increase in hardness and a reduction in toughness.

http://www.tppinfo.com/case_study/d_stability.html


so.. its a start... if you believe that place and their numbers

Greg

 

[Nathan the Machinist]

Greg,

That is some good reading. Thanks.

 

[delbert ealy]

Hi

i did some searching... and this google book came up..
http://books.google.ca/books?id=_a9...&oi=book_result&ct=result&resnum=10#PPA341,M1

on pg 341... it does show that two cryo/temper cycles to 203k reduce the RA from 4.3 to 3.3 in the 2nd cycle..

so from this article ...there is an affect.... ( it would be nice to see from multiple sources since theres already enough bizarre claims to do with cryo and unobservable phoenomena )

this site say's :

Mf (a temperature at which the transformation of martensite is essentially complete) lies between -80ºC and -110ºC. At the temperature down to -100ºC, retained austenite in the as-quenched microstructure transforms to martensite, resulting in an increase in hardness and a reduction in toughness.

http://www.tppinfo.com/case_study/d_stability.html


so.. its a start... if you believe that place and their numbers

Greg

Thanks Greg I may just have to buy the book now.
Del

 

[mete]

I don't consider a 1 % drop in RA to be significant ! My data of 20 % or more RA is from " Tool Steels" by Roberts ....
A careful control of austenitizing temperature , a cryo treatment , and a double temper will be as good as you can get.

 

[SteelSlaver]

Just curious... what steel would you pick, and why? (no, I'm not trying to start any arguments. )

I am not quite sure, but probably something like 52100. Tough stuff, that would be hard to break, when done correctly and it could be resharpened with some found stone. If you are in a survival situation and you let you knife rust your are going to die anyway. It would also only have about a 4" blade. So many other things would work better for defense and snares and dead falls would provide much more reliable protein sources. Even better than firearms