采用自行设计的喷射电沉积设备制备了镍枝晶沉积物,考察了不同试验参数对枝晶生长过程以及生成的枝晶形貌的影响,根据计盒维数原理计算了枝晶图片的分形维数.结果表明:较高的电流密度有利于枝晶的形成;随电解液中镍离子浓度的增加,生成的枝晶明显变得稀疏,分枝减少;枝晶形貌由致密紧凑型结构向疏松弥散型结构转变;随电解液温度的增加,沉积层逐步致密化.镍枝晶具有明显的分形结构,分形维数随着电流密度的增加而增大,随着电解液温度的增加先增大后减小,随着镍离子浓度的增加而减小.
Nickle dendrites were prepared by using a self-developed jet electrodeposition device, and the effects of different experimental parameters on the growth and microstructure of the dendrites were observed. Moreover, the fractal dimension of the dendrites in the pictures was calculated by means of the box-counting dimension method. The results show that (1) nickel dendrites are easy to form at a high density current; (2) the dendrites obviously become sparse with a decreasing fraetal number when the content of Ni ions in the electrolyte increases; (3) the microstructure of the dendrites changes from a compact and tight one to a diffuse and loose one; (4) with the increase of electrolyte temperature, the dendrites become more compact; (5) the dendrites are of obvious fraetal structure ; and (6) the fraetal dimension of the dendrites increases with the increase of current density and with the decrease of nickel ion content ; however, with the increase in the electrolyte temperature, it first increases and then decreases.