Metastable Structure of Soft Magnetic Fe_77-xNi_xCu₁Nb₂P₁₄B₆ Nanometer Polycrystals Induced by Mechanical Alloying

The local structures of the mechanically alloyed （MA） Fe_77-xNi_xCu₁Nb₂P₁₄B₆ soft magnetic materials were investigated by X-ray absorption fine structure （XAFS） The results show that during the ball milling, there are the same changes for the lotal structures of Fe and Ni atoms in a MA Fe_77-xNi_xCu₁Nb₂P₁₄B₆ sample. Mechanical alloying can drive the Fe_77-xNi_xCu₁Nb₂P₁₄B₆ powder mixture to produce a amorphous alloy while the atomic composition of Fe element is beyond 40%. In contrast, the MA Fe₂₂Ni₅₅Cu₁Nb₂P₁₄B₆ and Fe₁₂Ni₆₅Cu₁Nb₂P₁₄B₆ form alloys with a fcc-like structure, preserving a medium rang order around Ni and Fe atoms after 120 h ball milling. We find that the bee structuralα-Fe disappears and fcc structural Fe is formed for the MA Fe_77-xNi_xCu₁Nb₂P₁₄B₆ alloy while Fe atomic composition is lower than 22%. It indicates that a soft magnetic Fe_77-xNi_xCu₁Nb₂P₁₄B₆ nanometer polycrystal can be produced by MA.