稳恒平行磁场对循环电镀液Fe-Si复合电沉积的影响

Effect of Static Parallel Magnetic Fields on Fe-Si Coatings Prepared by Composite Electrodeposition under Cyclic Electroplating Solution

以不同硅含量的Fe-Si合金颗粒及纯Si颗粒为原料,在稳恒平行磁场下采用循环镀液复合电沉积法制备Fe-Si复合镀层,考察了磁场强度、颗粒硅含量、电流密度对Fe-Si复合镀层形貌及镀层中硅含量的影响。结果表明,在无磁场情况下,随着颗粒硅含量的增加,镀层中硅含量显著下降;施加平行磁场后,随着磁场强度的增加,Fe-50%Si(质量分数,下同)、Fe-70%Si和纯Si颗粒获得的镀层硅含量显著增加,而采用Fe-30%Si颗粒在磁场强度高于0.3 T后获得的镀层硅含量呈下降趋势。同时,在梯度磁场力和磁流体力学效应(MHD效应)协同作用下,Fe-Si颗粒在镀层表面呈圆丘状分布。当电流密度为2 A/dm^2、磁场强度为0.5 T时,采用Fe-50%Si颗粒电镀获得的镀层硅质量分数可达21.23%。

Fe-Si composite coatings were prepared by composite electrodeposition using Fe-Si alloy particles with different silicon content and pure Si particles in the cyclic plating solution under static parallel magnetic fields. The effect of magnetic field intensity,silicon content of particles,current density on the morphology and silicon content of composite coatings were investigated. The results showed that the silicon content of coatings significantly decreased in the absence of magnetic field with increase of the silicon content in particles. After applying the parallel magnetic field,with the increase of magnetic field intensity,the silicon content of Fe-Si coatings obtained by Fe-50% Si（ mass fraction,the same below）,Fe-70% Si and pure Si particles increased significantly,while that decreased gently for Fe-30% Si particles when the magnetic field intensity was higher than 0. 3 T. At the same time,under the synergistic action of gradient magnetic field force and magneto hydrodynamic effect（ MHD effect）,the Fe-Si particles were distributed in the form of dome on the coating surface.When the magnetic field intensity was 0. 5 T and current density was 2 A/dm^2,the silicon content of the coating obtained by plating with Fe-50% Si particles was up to 21. 23%.