Effect Of High Static Magnetic Field On Microstructure And Property Of Electrodeposited Sm-Fe Film

The researches on Sm-Fe inter-metallic compound have recently become ahighlight due to the excellent intrinsic magnetism and high magnetic anisotropy.Magnetoelectrochemistry developed in recent years is concerned with a novelelectrodeposition technology, which has attracted much attention to developingpermanent magnets with high performances. The electrodeposition process,microstructure and properties of planting layers are influenced remarkably by theinteraction between magnetic and electric fields. This thesis is focused upon preparationof Sm-Fe alloy film by elecrodeposition within an external high static magnetic field,with the effects of both strength and orientation of the high magnetic field onmicrostructure and properties of the deposed alloy studied, and the effecting mechanismdiscussed to provide the basis for a theory to explore a new preparation process.The electrochemical behavior of electrolyte was studied by cyclic voltammetry.The results of voltammetry and EDS analysis show that co-deposition of both Sm3+andFe2+occurs inductively, and the optimized parameters for the process have beenobtained.A high static magnetic field in different orientations (parallel or vertical to current)with different intensity were superimposed during the deposition of Sm-Fe alloys, theinfluence on electrodeposition process, microstructure and properties of the layers werealso investigated. The hydrogen evolution reaction was recorded by digital a camcorder,the microstructures were observed via SEM, the content of Sm was examined via EDS,the phase composition were characterized via XRD, and the magnetic property wastested by VSM.It was found that the surface morphology, component, microsructure and magneticproperty of as-deposited films were strongly affected by the high static magnetic field, and the magnetic flux density determines the final states of the plating layers. Moreover,magnetohydrodynamic (MHD) plays a key role when a superimposed magnetic field isperpendicular to the electrode surface. A vertical magnetic field to current leads to adominant effect in electrodepositon, while magnetization of a parallel field is moresignificantly than micro-MHD of a vertical one.