模板电解金属双极板表面流道的试验研究

Experimental Research on Electrochemical Machining by Mask of Metallic Bipolar Plates

随着燃料电池微型化的发展趋势,金属材料制成的双极板成为未来双极板发展的主要方向。以加工双极板表面多通道蛇形流道为例,提出采用模板电解加工金属双极板上的微流道结构。建立模板电解加工间隙内电场的数学理论模型,并利用有限元软件对模板电解加工微流道的成形过程进行模拟,研究加载电压对模板电解加工过程中阴阳极表面电场分布的影响。搭建模板电解试验平台,通过试验研究直流和脉冲加载电压对流道形貌和定域性的影响。模拟与试验结果表明,采用脉冲小电压可减小流道的杂散腐蚀,提高模板电解加工的定域性。

With the development trend of fuel cell miniaturization, the metallic bipolar plates are major development direction of the bipolar plates in the future. Take multi-channel serpentine flow field as example, an electrochemical machining process by mask was first proposed to fabricate micro-scaled flow channels on the metallic bipolar plates. A mathematical model of the electrochemical machining process by mask was established. The shaping process of micro-scaled flow channels and the influence of different interelectrode gaps on the electric field distribution was simulated by electrochemical machining method with finite element software. The experimental system was set up for electrochemical machining by mask. The location effects of DC and pulse voltage on morphology of channels were invested experimentally. Simulation and experimental results show that small pulse voltage can effectively reduce the dispersive corrosion and improve the localization of electrochemical machining by mask.