A-2 Tool steel?

[JV Rooster]

Is this a good knife steel? Is it stainless or does it rust. If I get a knife in this steel what is the best way to take care of it? Thanks

[kbaknife]

Sure - it's a good knife steel. There's a long list of good knife steels.
But none of them will be any better than the knowledge of the maker who forges, grinds and heat treats them.
Done correctly, it performs rather well.
It's classified as a stainless due to the amount of chromium it has.
It might rust if completely ignored.
The best way to take care of it is to get blood and guts all over it and then clean and dry it.

[KSCATTRAPR]

I've made several knives out of A2 and it works great. If heat treated correctly, it's very hard and holds a great edge. Take care of it and you will love the steel.

[Todd Robbins]

To be classified as stainless, a steel must have 14% chromium.  A-2 has around 5%.  It is a little more stain resistent than simple carbon steels, but it will tarnish readily.  It does hold an edge well and has pretty good impact toughness.  It was long considered the "go-to" steel for an air hardening steel that needed to be tough.  The CPM steels have taken over that position, now, but A-2 is still a good, solid steel.

[longbowman]

My last 6 knives were from A-2 and when you harden it to 58 Rc you'll have an edge that is sharp and will last.  Yes, it can rust but like any other knife if you take care of it it will do you fine.
 
These are both A-2

[kbaknife]

Todd, thanks for the clarification on that. What I find for "stainless" is steel with a minimum of 10.5%.
Regardless, I have a big round bar of A2 I've been tempted to forge into a knife for some time.
I just might go ahead on that one of these days.

[Todd Robbins]

The most technical definition of stainless I've seen involved a formula subtracting the carbon content % from the chromium content % to get the percentage of free chromium (not tied up in carbides).  Seems like it was about 13% ftree chromium, but I'm quoting from memory, so it could be off a little.  Of course, other carbide formers could affect that formula as well.  Regardless, A-2 is a fine knife steel, and Karl would be a great smith to forge blades out of it.  I'd love the opportunity to do some serious cutting with one of those blades, if you ever get around to it, Karl!