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

Until the early 20’s, metallic alloys were designed in a conventional way as far as their composition was concerned. At saturation level of their properties, the introduction of High Entropy Alloys (HEAs) challenge seemed to upgrade the commonly used alloy concept and transform the traditional view of metallic materials into an original breakthrough. HEAs have a broad range of structures and properties, and find use in multiple structural, magnetic, high-temperature, and oxidation-resistant applications. Due to their unique properties, these systems have attracted considerable attention both from academics and technologists.
In the present work, phase constitutions, either affected by alloying or structural changes, are explored as the key factors allowing to determine the mechanical and magnetic performance of the Additively Manufactured FeCoNi(AlMn)x systems. The microstructural features and crystal structures of the alloys were characterized, in both as received and heat-treated conditions. Hardness tests, under various indentation loads and dwelling times, were performed to assess the mechanical properties of the prepared samples. The work highlights a process-structure-property (PSP) relationship through creating hardness neural network profiles as a function of constituent elements concentration. Regarding the magnetic properties, the alloys exhibited good soft-magnetic behavior, being easily magnetized to the saturated state with coercivity values of <1000 A/m. Magnetic screening through Magneto-Optical Imaging (MOI), Magnetic Force Microscopy (MFM) and Vibration Sample Magnetometer (VSM) confirmed the importance of the structure evolution in defining the magnetic properties of the alloys. The trends in the magnetic behavior, as a function of the alloy composition are revealed.