High magnetostriction at low fields of epoxy/Tb1-xPrx (Fe0.4Co0.6 )1.9 composites

High Pr-content Tb1-xPrx(Fe0.4Co0.6)1.9 magnetostrictive alloys (0.7 < =x < =1.0) with a single cubic Laves phase have been synthesized by melt-spinning and subsequent annealing processes. The lattice parameter and the magnetization of the Tb1-xPrx(Fe0.4Co0.6)1.9 Laves phase increase while the Curie temperature, the magnetocrystalline anisotropy, and the spontaneous magnetostriction coefficient lambda111 decrease with increasing Pr-content. The characteristic of the magnetostriction lambdaa=lambda-lambda of the epoxy/Tb1-xPrx(Fe0.4Co0.6)1.9 composites can be well understood by the spontaneous magnetostriction lambda111 and the magnetocrystalline anisotropy of the Tb1-xPrx(Fe0.4Co0.6)1.9 alloys. The epoxy/Pr(Fe0.4Co0.6)1.9 composite free of high-cost Tb has a high magnetostriction of about 500ppm at 6kOe, suggesting that it would be a promising magnetostrictive composite material for low field application.