Investigation of Room Temperature Ferromagnetic Nanoparticles of Gd5Si4

Gd
₅
(Si
_x
Ge
_1-x
)
₄
compounds undergo first-order phase transitions close to room temperature when x ~ = 0.5, which are accompanied by extreme changes of properties. We report the fabrication of the nanoparticles of one of the parent compounds-Gd
₅
Si
₄
-using high-energy ball milling. Crystal structure, microstructure, and magnetic properties have been investigated. Particles agglomerate at long milling times, and the particles that are milled >20 min lose crystallinity and no longer undergo magnetic phase transition close to 340 K, which is present in a bulk material. The samples milled for >20 min exhibit a slightly increased coercivity. Magnetization at a high temperature of 275 K decreases with the increase in the milling time.