Hot isostatic pressing as a tool for enhancing the diffusion bonding of dissimilar materials using interference fitting as pre-joining technique

One nickel-based superalloy and austenitic stainless steel were joined together using a technique that didn't require any capsule or welding. The trial was performed with a low-pressure furnace and in a Hot Isostatic Press. The Press, a Quintus QIH 15 L, was coupled with the uniform rapid cooling module to join the two metals and deliver a suitable heat treatment for both alloys. In contrast to the low-pressure furnace, the application of the hot isostatic pressing effectively halved the processing time required for the joining procedure. This research highlights the critical roles of time and temperature in achieving a successful bond between the two dissimilar metals. The interface between the two metals was studied in depth with optical and electronic microscopy and Energy dispersivex-ray spectroscopy (EDS) to assess better the solid-state diffusion of the involved elements.