Abstract The new method of micro-shaft fabrication, named twin-mirroring-wire tangential feed electrical discharge grinding (TMTF-WEDG), is mainly characterized by the tangential feed strategy and the narrow slit formed by twin-mirroring-wire to achieve the diameter control of micro-shaft. The critical factors of micro-shafts accuracy and repeatability include processing position offset of micro-shaft, front edge position fluctuation of wire electrodes, and asymmetry of the twin-mirroring-wire electrodes, which cause the deviation of the tangential feed path and fluctuation in narrow slit width. The diameter of the micro-shaft was smaller than the theoretical value with processing position offset, which is not conducive to the control of the micro-shaft diameter. The front edge fluctuation of the wire electrodes caused the variation of the micro-shaft diameter to be around ±3 μm in the axial direction. The asymmetry of the twin-mirroring-wire electrode is the key factor affecting the tangential feed path which further affects the controlling the repeatability of the micro-shafts. New strategies were proposed, including the determination of the initial machining position achieved by tool setting, improvement of the twin-mirroring-wire system, the determination of the feed path, and improvement of feed strategy for trimming the taper of micro-shafts. The processing results show that a micro-shaft with a diameter of 45 μm and uniformity of ± 0.5 μm was successfully fabricated. For five repeated fabricated micro-shafts, the diameter repeatability was controlled within ±1 μm.

中文翻译：

---

双镜线切向进给电火花磨削加工微轴精度的提高

摘要 双镜线切向进给电火花磨削（TMTF-WEDG）微轴制造新方法，主要特点是切向进给策略和双镜线形成的窄缝达到直径微轴控制。影响微轴精度和重复精度的关键因素包括微轴加工位置偏移、线电极前缘位置波动、双镜线电极不对称等导致切向进给路径偏差和加工精度波动。狭缝宽度。加工位置偏移时，微轴直径小于理论值，不利于微轴直径的控制。电极丝的前端波动导致微轴直径在轴向上的变化约为±3 μm。双镜线电极的不对称性是影响切向进给路径的关键因素，进而影响微轴重复精度的控制。提出了新的策略，包括通过对刀确定初始加工位置，改进双镜线系统，确定进给路径，以及改进微轴锥度修整的进给策略。加工结果表明，成功制造出直径为45 μm、均匀度为±0.5 μm的微轴。对于五个重复制造的微轴，直径重复性控制在±1 μm内。