Design, fabrication and evaluation of Fe-Mn-Mo-Zr-Ti-V-B type additive manufactured mixed metal boride ceramics

This study presents new high entropy ceramics that have a great potential to play an important role in high temperature resistant ceramics in advanced engineering applications. Instead of alloying with one or two elements, alloying with five or more principal elements in equiatomic concentration results in the formation of transition metal high entropy monoborides (HEMB), which exhibit superior mechanical properties in high temperature, oxidative, corrosive, and high wear environments. Among various ceramics, transition metal borides exhibit excellent mechanical strength and wear resistance. The authors have chosen Fe-Mn-Mo-Zr-Ti-V-B type ceramics for investigation and in this paper, various design criteria, fundamental understanding of their formation, comparison of simulated mechanical and elastic properties as well as performance data of additive manufactured (AM) samples are presented. It was observed that new boride-based ceramics are robust and relatively stable as evident in their thermodynamic properties and first principle-based simulations. It was observed that both average Young's and shear moduli are relatively high for (Fe0.16-Mn0.16-Mo0.16-Zr0.16-Ti0.16-V0.16) B. Anisotropy is more prominent in the case of (Fe0.16-Mn0.16-Mo0.16-Zr0.16-Ti0.16-V0.16) B. Corrosion performance of material and hardness testing was performed for preliminary evaluation of AM samples, which suggest a better performance for boride-based ceramics.