(上海大学 上海市现代冶金与材料制备重点实验室, 上海 200072)
摘 要: 在电沉积镍铁合金膜过程中施加了不同强度的纵向强磁场, 研究了磁场强度对电沉积镍铁合金膜的微观形貌、 晶粒取向和成分的影响。结果表明: 随着磁感应强度增加, 镀层表面晶粒先粗化, 然后细化为数百纳米的颗粒层; 同时样品截面组织经历了由层状生长转为树枝晶、 脊状晶和条状晶的一系列变化;在12T强磁场下条状晶沿外磁场方向破碎为球状微晶组织; 强磁场使样品(111)晶面择优取向, 并进一步促进了Fe2+的优先沉积,使样品中铁含量随外加磁场强度的增大而增加, 而膜的饱和磁化强度也线性提高。
关键字: 镍铁合金膜; 强磁场; 电沉积; 微观结构
( 1. Shanghai Enhanced Laboratory of Modern Metallurgy and Material Processing, Shanghai University, Shanghai 200072, China)
Abstract: NiFe alloy films were electrodeposited in the high static magnetic fields with magnetic flux perpendicular to the electric current, and the effects of the magnetic flux density (MFD) on the micromorphology, preferential orientation, composition and saturation magnetization of the samples were studied. The results show that, with the increase of MFD, the crystal grains on the surface of the samples are coarsened firstly, then refined, and finally formed spherical crystal grains with several hundreds of nanometers in size, distributing uniformly. At the same time, the microstructure of across-section experiences a series of changes from lamellar crystal to fir-tree crystal to carinate crystal and finally to strip structure, and when MFD reaches 12 T, the strip crystals are broken along the magnetic field direction and form spherical microcrystallites. With increase of MFD, the crystal plane(111) is oriented distinctly, and Fe2+ ion is preferential deposited with the increasing static magnetic field, which results in the increases of iron concentration and saturation magnetization of the samples.
Key words: NiFe alloy film; high static magnetic field; electrodeposition; microstructure