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

A method for hot isostatic pressing includes the steps of providing or obtaining an article of manufacture, which optionally includes a copper or nickel alloy, disposing the article of manufacture in a shroud, the shroud defining an enclosed volume wherein the article of manufacture is disposed, the shroud being configured as a multi-piece joined structure to retard gaseous mass transport from outside the shroud to inside the enclosed volume, disposing the shroud in a containment vessel of a hot isostatic pressing apparatus and disposing a getter material in the shroud and/or in the containment vessel, and introducing an inert gas at an elevated temperature and pressure into the containment vessel for hot isostatic pressing.