Metal Additive Manufacturing Conference - MAMC 2023

Alloy-X is a well-established nickel-based superalloy that is extensively used in petrochemical- and aerospace industry due to its outstanding combination of corrosion resistance and high temperature performance. Since additive manufacturing is more and more establishing itself as a capable method for producing components with complex geometries, also the properties of 3D-printed samples must be investigated.
Therefore, samples of three different chemical compositions of alloy-X were additively manufactured via LPBF, examined and compared regarding their microstructure and mechanical properties. A particular focus was laid on the susceptibility to hot cracking in the as-built condition, which seems to increase with increasing impurity, namely sulfur content, and negatively affects the impact toughness of the material. This was manifested, by dendrites on the fracture surface. Consequently, hot isostatic pressing was used to close the cracks and potentially enhance the mechanical performance of this alloy variant.
Furthermore, high-temperature tensile tests were carried out to determine the behavior at elevated temperatures above 750°C and to derive the influence of the alloying elements. Here, the potentially positive influence of hot isostatic pressing on the properties of the impure, sulfur-rich variant was also investigated.