Net shape HIPping of Ni-superalloy: Study of the interface between the capsule and the alloy

Abstract

Nowadays, an increasing number of components are manufactured using Hot Isostatic Pressing (HIP), which is considered a near net or net shape forming technology, depending on the overstock thickness. One of the most challenging tasks with regard to improving HIP is limiting the interaction between the capsule and the consolidating powders, aiming to reduce material waste and costs. The capsule is typically made of mild carbon steel and it is used to correctly transfer the forming pressure to the loose powders at the HIP temperature. The great inhomogeneity between the two materials at such a high pressure and temperature lead to a strong elemental diffusion between the powders and the capsule, which leads to the formation of an interface. This study investigates in depth, the effects of this diffusion during the consolidation of Astroloy powders