Investigation of magnetization reversal in Sm-Fe-Cu(Zr)-Ga-C nanocomposite magnets

Abstract

A comparative study has been performed concerning the microstructure and the magnetization reversal behavior of nearly single-phase Sm2Fe14.5Cu0.5Ga2C2 and two-phase exchange-coupled Sm2Fe14.5Cu0.5Ga2C 2/α-Fe and Sm2Fe14.25Zr0.25CU0.5Ga 2C2/α-Fe synthesized by melt spinning and annealing. A few percent of Zr substitution proved to be effective in refining the microstructure and enhancing exchange-spring behavior after melt spinning and annealing. All samples show remanence enhancement, the value of Mr/Ms being the largest for the sample containing Zr. Measurements of the reversible susceptibility show a large reversible magnetization in the two-phase materials. For the Zr-containing sample, a more detailed analysis of the temperature dependence of the exchange-spring behavior was made. © 2000 American Institute of Physics.