关键词: 掩模电解, 群柱体织构, 干膜模板, 加工质量

Abstract: Micro-texture is widely used in friction and wear,thermal energy exchange,sealing of key components,biomedicine and many other fields. As a kind of micro-texture,cylinder texture plays an important role in increasing friction.Taking advantage of high electrochemical machining efficiency and no residual stress,a dry film mask electrochemical machining method of group cylinder texture was proposed.MS series dry film with high adhesion was selected to prepare mask,and the multi-physical field coupling analysis of flow field,electric field and reactant transfer was carried out. The effects of different template thickness on the electrolyte flow velocity,bubble rate and conductivity in the processing area were studied. The analysis results show that the template with 50 μm thickness can bring higher electrolyte flow velocity on the surface of the workpiece,accelerate the discharge of products and bubbles,and electrical conductivity of the workpiece surface is higher. The effects of processing voltage,processing time and pulse duty cycle on the size of group cylinder texture were studied by experiments.The experiment results show that under the processing voltage of 25 V and the processing time of 15 s,the group cylinder texture with good localization can be obtained,and moreover,the mass transfer process of insoluble electrolysis products,bubbles,and electrolyte is further improved under the pulse electrolysis processing with a pulse duty cycle of 20 % and a pulse frequency of 4 kHz. Finally,under the preferred processing parameters of 25 V processing voltage,15 s processing time,20 % pulse duty cycle,and 4 kHz pulse frequency,a group cylinder texture array with a diameter of 320.48 μm,a height of 15.06 μm,and a lateral corrosion coefficient EF=1 was processed on the TC4 surface.

Key words: mask electrolysis, group cylinder texture, dry film mask, machining quality