Effect of composition and powder size on magnetic properties of rapidly solidified copper-iron alloys

Microstructure and properties of Cu-Fe alloys fabricated via powder metallurgy and rolling

“…The relatively high coercivity ( H c ) and low electrical conductivity of the alloy prepared by atomised powders may be related to defects such as lattice distortion caused by thermal stress during rapid solidification. The lower CFA prepared by this process than reported by Kim et al [10] may be due to higher sintering temperature, easier precipitation of atoms dissolved in the matrix after hot rolling, smaller lattice distortion and smaller resistance of domain wall displacement. Therefore, the CFAs prepared in this study had excellent functional properties and good mechanical properties.…”

“…The Fe particles were elongated along the deformation direction after cold rolling, and the magnetic domain showed stronger magnetism, so the magnetic saturation strength was larger. The reason for the higher electrical conductivity than reported by Kim et al [10] may be that due to the high sintering temperature and long time, so Fe dissolved in Cu precipitates more easily, and a large number of dislocations and other defects were produced after later deformation processing, which was more conducive to the precipitation of Fe, and the Cu matrix had fewer solid solution atoms, resulting in higher electrical conductivity. The relatively high coercivity ( H c ) and low electrical conductivity of the alloy prepared by atomised powders may be related to defects such as lattice distortion caused by thermal stress during rapid solidification.…”

“…Additionally, the phase interface increased with the Fe content, resulting in greater structural distortion. In the process of the domain wall displacement or rotational magnetisation, these phase interfaces and distortions hindered the domain wall displacement, and dislocations would also bring about the increase of spin pinning position, which were the reasons for the increased coercivity [10].…”

“…The results show that the tensile strength was 1216 MPa, and the electrical conductivity was 47.6% IACS when the total deformation strain was 6. The study of Kim et al [10–12] shows that the electrical conductivity and magnetic properties of CFAs increased with the decrease of the size of gas atomisation alloy powders. When the powders particle size was less than 24 μm, the electrical conductivity of CFA 30 was 20.1% IACS, the magnetic saturation strength (Ms) was 57 emu g −1 , and the coercivity ( H c ) was 256 Oe.…”