from the conferences organized by TANGER Ltd.
This work focuses on the development and characterization of functionally graded materials (FGM) produced by combining the nickel-based superalloy MoNiCr and the austenitic stainless steel 316L using the DED LB/W additive manufacturing technology. The aim was to verify the technological feasibility of multi-material printing of two metallurgically distinct alloys, evaluate the quality of the interface between them, and assess the influence of deposition order and subsequent heat treatment on the resulting microstructure and hardness distribution. The results show that the deposition order significantly affects the nature of the transition zone. When depositing 316L steel onto the MoNiCr nickel alloy, a wider mixed layer is formed, which is related to differences in melt pool dynamics and thermal gradients. The opposite order—i.e., depositing MoNiCr onto 316L—results in a more sharply defined interface with a lower degree of chemical mixing. Subsequent heat treatment caused significant homogenization of the microstructure associated with recrystallization and led to the equalization of hardness across both materials, thus minimizing local differences created during printing. The findings confirm that the combination of MoNiCr and 316L is technologically suitable for the DED LB/W process and enables the production of stable functionally graded structures with a controllable transition between materials. These results represent an important step toward the development of components for the energy sector, where localized tuning of material properties can be utilized—for example—for parts exposed to high temperatures and aggressive fluoride salts in Generation IV systems.
Keywords: additive manufacturing; nickel-based superalloys; DED technologies; MoNiCr alloy, functionally graded materials© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.