有限元在金属微结构电铸特性分析中的应用

为改善高深宽比金属微结构的电铸成型质量,采用有限元方法分析微细电铸的电场和流场的分布特点,及搅拌方式、电场和流场分布对微细电铸质量的影响。研究表明:搅拌对电铸区域的影响只集中在微区的入口部分,深度小于55μm,扩散过程成为金属沉积的限制性因素;电力线曲率随电铸深宽比增大而提高,导致电铸微区内金属离子传输能力不均匀。微细电铸过程中,搅拌速度提高并不能改善金属沉积的传质条件;辅助超声的复合搅拌在相同条件下能提高金属沉积速度,减少铸层缺陷、改善传质。实现了表面光滑、侧壁陡直的金属微结构的电铸成型。

FEM Analysis on the Electroforming Property of Metallic Microstructures

To improve the electroforming quality of the metallic microstructure with the high aspect ratio,the distribution characteristics of the electric field and flow field in the micro electroforming and the effects of the stirring,electric field and flow field distribution on the micro electroforming quality were analyzed by FEM.The results show that the effect of the stirring on the electroforming area is only centralized the entrance of the micro area with the depth less than 55 μm,and the diffusion process becomes the restrictive factors of the metal deposition.The equipotential line curvature increases with the increasing aspect ratio of the electroforming,which results in the discrepancy of ion transferring capacity in the reaction area.In the micro electroforming process,the increase of the stirring velocity could not improve transferring condition of the metal deposition,while complex stirring with auxiliary ultrasonic could improve the velocity of the metal deposition and reduce the defect of the electroforming layer to get the perfect microstructure.The electroforming of the metallic microstructure with smooth surface and vertical side wall was realized.