About this Abstract |
Meeting |
Materials Science & Technology 2020
|
Symposium
|
Light Metal and Composites Technology
|
Presentation Title |
Metastable f.c.c. Phase and Its Influence on the Soft-magnetic Properties of FeCoNiAlxSix (0.2 < x < 0.5) Alloys |
Author(s) |
Tanjore V. Jayaraman, Ramasis Goswami |
On-Site Speaker (Planned) |
Tanjore V. Jayaraman |
Abstract Scope |
Significant improvement in soft-magnetic properties of FeCoNiAlxSix (0.2 < x < 0.5) high-entropy alloys is achievable when the alloys are comprised of metastable f.c.c. phase. The nanocrystalline FeCoNiAl0.375Si0.375 alloy fabricated by mechanically alloying the constituent elements resulted in the formation of metastable f.c.c. phase. The metastable phase was stable up to ~800 K and thereafter it dissociated. At ambient temperature, the magnetic saturation (MS) and coercivity (HC) of the alloy was ~91 Am2/kg and ~5 kA/m, respectively. The magnetic characterization from 60 K to 900 K showed a steady decrease in MS, and the HC initially decreased and subsequently increased. The thermally-treated alloy exhibited improvement in the soft-magnetic properties while retaining the nanocrystallinity. While fabrication of the alloys by equilibrium processing facilitates the formation of two phases—b.c.c. and f.c.c., fabrication by mechanical alloying promotes the formation of metastable f.c.c. phase having relatively superior soft-magnetic properties and good thermal stability. |