Vacuum age hardening of PH grade stainless steels requires two or more steps. First, the material is solution annealed at temperatures up to 1950℉ in a vacuum followed by a rapid gas fan cooling down to ambient. The material is then heated to the aging temperature (between 900℉ and 1150℉ depending on the grade) and held for several hours. Some grades require cryogenic treatment or other intermediate steps.
NATIONAL HEAT TREAT has two (2) vacuum furnaces capable of vacuum age hardening.