Heat Treat 4140 Non Knife

[Alex Cole]

I have a heat treat oven so It is hard to test for non magnetic without loosing all of the heat inside. I was wondering if anyone knows how to heat treat and temper 4140 to a 45-55 rocwell?

Thanks

alex

[Ray Rogers]

That's not a steel that most blade makers would have much experience using. A quick search of the internet revealed that heating 4140 to 1550 F, followed by an oil quench, and tempered for 30 minutes at 400 F will give a Rc of near 40. At a guess I'd say it probably wouldn't get to Rc 55 even at full hard and, if it did, it would probably be brittle. Since it's not a blade steel you may not find much info on it here so, as with so many things in knife making, you'll just have to experiment to see if you can get what you want out of it....

[Alex Cole]

Thanks for the info. I am trying to help a local shop out with some parts.

thanks

alex