微细掩膜电解加工的孤岛有限元仿真研究

摘要

在微细掩膜电解加工初期，被加工表面会形成孤岛结构，不利于加工出形状、精度良好的浅表面微结构，故减小电解加工过程中的孤岛结构很有必要。采用有限元方法建立了微细掩膜电解加工的数学模型，并利用该模型分析掩膜厚度和加工间隙对孤岛变化的影响，进而推论出电解加工开始时，被加工面上不均匀的电流密度分布是形成孤岛的原因。通过增加被加工表面的电流密度的均匀性，可提高浅表面微结构的加工质量。%In the early stage of micro-mask electrochemical machining ,machined surface will form an island,the structure is not conducive to forming micro structure of shallow surface shape with good precision,so it is necessary to reduce the effect of the island in ECM. A mathematical model of micro-mask electrochemical machining is established by finite element method ,and the effect of mask thickness and machining gap on the island are analyzed by this model ,and then a conclusion is made that the cause of the island is the uneven distribution of current density on machined surface at the start. The precision of shallow surface can be improved by homogenizing current density.