Structure and magnetic properties of mechanically alloyed Tb0.7Pr0.3(Fe0.9B0.1)1.93 and the magnetostriction of its epoxy composites

The C15 Laves phase with composition Tb0.7Pr0.3(Fe0.9B0.1)1.93 has been synthesized by mechanical alloying and subsequent annealing process. The structure and magnetic properties of Tb0.7Pr0.3(Fe0.9B0.1)1.93 have been investigated. The effect of the annealing on the magnetic properties has been studied. The samples annealed at 773 K are found to have a coercivity of 6.66 kOe at room temperature. The coercivity decreases monotonically with increase in the annealing temperature. The epoxy/Tb0.7Pr0.3(Fe0.9B0.1)1.93 composites have been produced by a cold compression-molding technique. The magnetostriction of the epoxy/Tb0.7Pr0.3(Fe0.9B0.1)1.93 composites with different weight ratios of epoxy resin to powder is measured by a standard strain technique. The Tb0.7Pr0.3(Fe0.9B0.1)1.93 composites, with a weight ratio of epoxy resin to powder of 5:100, have a high magnetostriction of 810 ppm, at an applied magnetic field of 12 kOe. The Tb0.7Pr0.3(Fe0.9B0.1)1.93 alloy combines a high magnetostriction with a low coercivity, which is a promising magnetostrictive material