Stainless Steel in a Forge?

[irishknifeworks]

Is there a stainless steel that can be heat treated in a gas forge? If so, how do I do it?

[Ray Rogers]

No, there isn't. Stainless steels all require extended soak times at precise temperatures and that's not possible in the average gas forge. You can heat up a piece of stainless and quench it one way or another and it will get hard but it won't be 'right'. It won't have the crystalline structure it should have and that means it could be brittle. It won't be as stainless as it should be (stainless isn't very stainless until after the heat treat is complete - and correct). And, of course, it isn't likely to be as hard and as tough as it should be. In short, you won't get what you paid for ...

[Doug Lester]

To build on Ray's reply. Stainless steels and complex tools steel generally need to be preheated to prevent uneven heating and crossing the A1 point at different times. This produces stress that can produce cracking. They may also need to be austinized at around 1800-1900? degrees and held at a steady temperature for one half hour to an hour.

Really, for forge heat treating you need to content yourself with simpler steels, nothing much more complex that the 10XX series, with a carbon content of not more than 85 points. That's not to say that it can be done, it's just difficult to do consistently.

Doug

[irishknifeworks]

Thanks guys, what would be your recommendations for which stainless to use for an inexperienced stainless knife maker and a heat treat service to send it to?

[Ray Rogers]

440C hands down, no contest. I'm picking that steel because of it's very simple (for stainless) heat treat and the fact that Texas Knifemakers will do the heat treat for about $5. If you pick one of the more complex stainless steels like S30V you could be disappointed by the heat treat a commercial outfit would choose to do. Complex steels can usually be HTed in several ways, some simple, some more difficult. Commercial outfits generally choose the simplest, fastest, cheapest way and that just doesn't get everything out of the steel that you paid for. So, stick with 440C or one of it's clones like 154CM until you have your own oven ...

[irishknifeworks]

Thanks guys. I've been primitive for years, just using 10.. and 01 basically. If you don't try new things you get stale. Just registered with the forum and have already learned a lot. Don't know why I haven't tried stainless sooner. I've had a lot of requests for it. Better late than never I guess.

[Crex]

Just a ? Irish, are you planning on forging a blade out of stainless or doing stock removal?
I ask because it seems most of your recent post have been more oriented toward forging than grinding.
You won't find the stainless alloys very friendly to general forging techniques....they have a very small window of temp range in which they are forgable without permanent stress damage.

[irishknifeworks]

Stock removal. Thanks.