镍电沉积界面层流/气泡-形核生长模拟研究
Simulation of laminar flow/bubble-nucleation and growth at the interface of the nickel electrodeposition
梁晓雨 1徐波 1赵明 1于佳正 1张斌1
作者信息
- 1. 北方工业大学 机械与材料工程学院,北京 100144
- 折叠
摘要
为探明镍电沉积过程中电沉积基体/电沉积液界面低流速层流场内电沉积副反应产生的气泡演变规律、Ni2+浓度场变化和镍晶体形核及生长特点,建立了电场、低流速层流场、浓度场、气泡/沉积液/镍晶体多相场的气泡/层流-镍晶体形核生长模型,并利用有限元方法计算该模型.结果表明,当形核前的气泡从镍基体脱附到浓度扩散层边界时,在气泡脱附位置周围气泡迎流区和背流区的基体表面镍以瞬时形核方式形核,当离开Ni2+浓度扩散层后,其产生的低Ni2+浓度区与层流对流和Ni2+扩散作用使镍晶体沿Ni2+流动最大方向择优生长,在气泡迎流区的枝晶高度最高.与此不同,形核后的气泡从镍基体脱附到浓度扩散层边界时,气泡产生的涡流只能使已经形核的晶体不均匀生长;当离开Ni2+浓度扩散层后,随后镍晶体以枝晶形式生长,沿Ni2+流动最大方向枝晶的生长速度最快.
Abstract
In order to investigate the evolution of bubble,the variation of Ni2+concentration field,the characteristics of nucleation and the growth of nickel crystals at the substrate/electrodeposition solution interface in the low-flow laminar flow during the process of nickel electrodeposition,a simulation mod-el of bubble/laminar flow-nickel crystal nucleation and growth coupled electric field,low-flow laminar flow field,concentration field,and bubble/solution/nickel crystal multiphase field has been estab-lished,which was calculated using the finite element method.The results showed that during the period of the pre-nucleation bubble desorbing from the nickel matrix to the boundary of the concentration diffu-sion layer,the nickel atoms on the surface of the matrix in the bubble upstream and downstream zones nucleated according to a transient nucleation mode,and when left the Ni2+diffusion layer,due to the low-Ni2+concentration zone and the effect of laminar convection and Ni2+diffusion,the nickel crystals grew preferentially along the direction of Ni2+flow then form nickel dendrites,The highest dendrites were found in the bubble upstream zones.Compared with this results,in the course of the post-nucleation bubble detaching from the nickel matrix to the boundary of the diffusion layer,the eddy current generated by the bubble can only cause the nucleated nickel crystals to grow unevenly;after bubble left the Ni2+concentration diffusion layer,the nickel crystals subsequently grew in the form of dendrite,and the rapidest growth direction of nickel crystals depended on the direction of Ni2+flow.
关键词
多场耦合/镍电沉积/模拟/气泡/流场Key words
multi-field coupling/nickel electrodeposition/simulation/bubbles/flow field引用本文复制引用
出版年
2024
NETL
NSTL
万方数据