[jimmontg]

Texas Knifemakers Supply sells a lot of chinese made knives made out of 9crMoV or 7cr17MoV and a cryo after a full HT does not make the knife brittle. I spoke to Alex at TKS about it as I figured it is just a sales gimmick, but he assured me that most of the non-super steels do not get brittle or lose toughness. It is why I said there are certain caveats to a final cryo with no temper.

I can have Dtec do a bend test on the knife or send it to me. I have had no problems with the cryo'd knives I have bought from TKS and they are all above RC 58 which is my bottom line for a knife for most applications. I had Dave do the experiment to see if what they were saying was true. Alex at TKS said where the problems comes in is if there is a high amount of Vanadium in the steel. A chef's knife I bought from them was quite flexible and over 58 hardness and it had <.20 V in it which makes a difference if the carbon is high enough, but not a huge one. It all boils down to the chemistry of the metal.

I would not have even brought it up without some background analysis and checking. I am not even sure if Dave did an initial Cryo on the 440C so I'll let him speak to his HT, but he has 440C down pretty good and is getting better all the time with some other steels. I know a temper is called for after cryo, but with some metals, like the cheaper Chinese stuff, cryo doesn't hurt as much as it improves. It certainly improved Dave's 440C and I would imagine some other steels would benefit from it and others would not like S30V.

The bottom line is a kit knife with a cryo treatment will be better than the same knife without it. I was just trying to tell nhatvoone (?) that the best non custom bread knife he can buy is from TKS. I bought one as a gift and it was the best bread blade my Uncle had ever seen. Jantz sells the same knife without the cryo. I most certainly am not telling a budding knifemaker to cryo a blade with no temper, I should have been more clear.