Welcome to KnifeDogs


A Family Friendly Knife Oriented Community Founded For Knifemakers, Collectors, & Enthusiasts.


  •  » Forums for individual knife dealers.
  •  » Forums for businesses supporting the knife industry.
  •  » Knife makers individual forums for visiting, support and sales.
  •  » Forums for knives.

...then you have come to the right place!


we will try to help you with your problem.


YES! I want to register an account for free right now!


Page 1 of 10 123 ... LastLast
Results 1 to 10 of 91

Thread: Cryo?

  1. #1

    Cryo?

    Might be a silly question but do you have to cryo the stainless? And steels like d2? Thank Davey


  2. #2
    Join Date
    Sep 2009
    Location
    Central Louisiana (Pollock)
    Posts
    1,447
    It isn't an absolute necessity but it really helps. The purpose is to convert a greater percentage of Austenite to Martensite. Tempered Martensite is the phase of steel that makes the best knife blade and the greater the Martensite percentage, the better the blade.
    Blades without a freeze/cryo can have as much as 15% retained Austenite and blades done with a freeze/cryo can have as little as 2%. Actual percentages vary widely depending on the steel and H/T procedure.
    Darrin Sanders
    190 Alma Drive
    Pollock, LA 71467


    318-233-0636

    darrinsanders8666@gmail.com

  3. #3
    Thank you so much for the reply. I will get some dry ice and start doing it when I start with those steps

  4. #4
    Join Date
    Sep 2009
    Location
    On the St. Johns river, Geneva , FL
    Posts
    485
    Actual cryo requires more than just dry ice.

  5. #5
    Join Date
    Jan 2012
    Location
    S. Baldwin Co., Alabama
    Posts
    1,857
    Take a look at this post to see what difference the real world has between dry ice (-95F) and no freeze treatment:

    http://knifedogs.com/showthread.php?...ub-zero-quench

    Start at top, watch cutting test for freeze treated blade, then on down to video of test with non-freeze treated blade. Then read what the guy says. Understand, this is NOT a scientific test, but more what a person would experience in real life.

    Ken H>

  6. #6
    Thank you guys

  7. #7
    Join Date
    Mar 2015
    Location
    NC
    Posts
    20
    Quote Originally Posted by Darrin Sanders View Post
    It isn't an absolute necessity but it really helps. The purpose is to convert a greater percentage of Austenite to Martensite. Tempered Martensite is the phase of steel that makes the best knife blade and the greater the Martensite percentage, the better the blade.
    Blades without a freeze/cryo can have as much as 15% retained Austenite and blades done with a freeze/cryo can have as little as 2%. Actual percentages vary widely depending on the steel and H/T procedure.
    It really depends on how optimal the maker wants the blade to be and the difference can be seen in testing.

    Ideally the blades should be kept in LN2 for 24 hours before the tempering cycles begin.

    However there are different thoughts on this as in to do it at all or not so opinions will vary, but if the maker want the highest performing blade possible then a proper CYRO is really needed.

  8. #8
    Its generally though to improve things, but some users report non-cryogenically treated blades hold their dges longer. It's not a "have to" thing though.

  9. #9
    Join Date
    Mar 2015
    Location
    NC
    Posts
    20
    Quote Originally Posted by me2 View Post
    Its generally though to improve things, but some users report non-cryogenically treated blades hold their dges longer. It's not a "have to" thing though.

    Would depend on who actually made the blades I would suspect and if the knife maker really knew what they were doing or actually had the proper Heat Treating equipment and if they used dry ice or LN2 and actually did it right or not.

    So things can vary.

  10. #10
    All that comes into play. I'm thinking specifically of a tester on another forum who had a well known heat treater take care of several blades, which he then tested to see the effects of various things, one of which was cryogenic treatment. I'd have to assume the heat treater he used knows what they're doing, as they heat treat a lot of knives for a lot of makers. I would share the names, but I'm not sure it's okay since it's on another forum, and I don't think the guy's a member here. In any case, in a carefully controlled test, cryogenically treated blades outcut non-treated blades in less than half his trials. This was a huge undertaking and it's not done as far as I know. The micrographs and analysis are still in the works.

    In terms of is cryogenic treatment necessary, about the only thing that can be said with great certainty is one has to try it out and see.

Page 1 of 10 123 ... LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •