EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Additive manufacturing (AM) by laser powder bed fusion (LPBF) involves melting of layers of material onto a substrate, called a building platform. Due to cost or convenience considerations, building platform materials rarely match the LPBF material, especially for high temperature/strength materials. As it is often required that an additively manufactured component is stress-relieved/heat-treated while still attached to the build platform to assure tolerances in component geometries, it is important to understand the effect of dissimilar building platform materials on properties of the built-up material. These effects may be particularly important for high performance materials such as Ni-base superalloys used for critical applications in the aerospace and energy industries. To investigate this effect, samples of a Ni-base superalloy were built onto steel and Ni-alloy building platforms. The samples were removed from the building platform after heat treatment and subjected to detailed microstructural characterization to investigate the effect of the building platform material on the properties of the additively manufactured part. Room temperature tensile testing, high temperature tensile testing, as well as hardness testing were used to characterize the material. The chemical composition profile using X-ray photoelectron spectroscopy (XPS) from the build plate into the deposited material was carefully traced.