S30V Heat Treat

Jerry,

What's the skinny on heat treating S30V. Is it something that could be done in shop with a regular HT oven?

Bob Sigmon

You can harden at 1975F for maybe 15-20 minutes, then quench. Temper at 450-500F. It doesn't seem to be very critical. The most important thing is the quench. You need to use quench plates to get the heat out of the steel fast. Using tool wrap there's just no other way to do it. The problem with quench plates is if you taper your tangs they don't work. You don't have enough contact to draw away the heat.

Keep in mind that I don't do my own heat treating, but the above is what I understand from others works.

Do you think that rapid moving air (from compressor) in combination with plates would be fast enough? I know that you don't have direct experience but you probably have a better educated guess than me. Any ways just a thought......

Thanks for your time,

Bob Sigmon

Bob, the plates should do it. The problem is the tool wrap. It's an insulator, so the plates are needed to get direct contact with the steel.

So if you were to skip the cryo how much of a hit would the blade take performance-wise? What percentage would you say? Right now it's not worth it for me to get the nitrogen dewar and I don't feel like trying the acetone and dry ice thing. But I can do the other part so I'm thinking of trying the heat treat myself.

Peter, you'll probably lose a point or two of hardness. Fast quench is more critical. It's my understanding, from others, you can put the blade in your freezer for about a week and gain most of the benefits of cryo. You might want to try that.

Cool! Literally! I'll give it a try Jerry. I'm thinking that I'll pick up a cheapy woodworker's vise with the wide flat jaws. That should do the trick for the quench if I'm doing just one or two blades.

Peter,

I am certainly no metalurgist but have talked to the metalurgists at Crucible and gather that a dry ice cryo is as cold as necessary for a cryo treatment as long as it is for a minimum of 6 hours. I simply sandwich the blades between two pieces of dry ice placed in a two dollar styrofoam cooler overnight. It usually runs me about $10-12 per batch for the dry ice which is a cheap price to pay for treating multiple blades.

It sounds like the fast quench necessary to partical steels causes enough retained austenite that a cryo treatment is beneficial. I don't have the equipment necessary to test this but since this method of cryo is so inexpensive, I always do it with S30V.

Gary