Can austenitic stainless steels (i.e. 300 series) be "hardened"?
Yes. The 300 series stainless steel can be "hardened" but only by "work hardening." This is done by cold working the material. This can be done by cold rolling to lighter thicknesses, cold "drawing" through a die, deep drawing a sink, pressing a pattern into the surface (i.e. embossing) or by an other operation that changes the metal’s shape while it is cold. "Annealing" stainless steel will remove this work hardening effect.