Hot isostatic pressing apparatus and hot isostatic pressing methods for reducing surface-area chemical degradation on an article of manufacture

A hot isostatic pressing apparatus comprising:

• a sealable containment vessel comprising a first gaseous atmosphere comprising an inert gas and trace amounts of a reactive gas, the first gaseous atmosphere being at a first temperature and a first pressure, wherein the containment vessel has standard atmospheric gasses withdrawn therefrom;
• a first shroud disposed in the containment vessel, the first shroud defining a first enclosed volume, wherein the first shroud is configured as a multi-piece joined structure that retards gaseous mass transport from outside the first shroud to inside the first enclosed volume, the containment vessel outside of the first shroud defining a second enclosed volume;
• a getter material disposed within the containment vessel but outside of the first shroud, wherein the getter material has an amount of the reactive gas chemically or physically adsorbed thereto;
• and
• a solid, non-powdered metal alloy or ceramic article of manufacture having a surface area disposed in the first enclosed volume of the first shroud,
• wherein at the first temperature and the first pressure, the shroud inhibits gaseous mass transport from the second enclosed volume to the first enclosed volume such that the inert gas in the second enclosed volume is at a higher temperature than the inert gas in the first enclosed volume, and wherein the hot isostatic pressing apparatus is configured to maintain the second enclosed volume at the higher temperature for a period of time of ten minutes to ten hours during which time the temperature in the first enclosed volume is configured to increase such that the first and second enclosed volumes substantially equalize in temperature after the period of time.