Fabrication of Blind Multi-microgrooves by Applying Long-Laminated Electrode

In this study, a combination of wire electrical discharge machining (WEDM), dry WEDM, and wear-variation EDM (WV-EDM) was proposed. This combined process allowed the cost-effective fabrication of Long-laminated elec-trodes (LLEs) with significant interference resistance and long service life, and subsequent stable large-scale production of deep and narrow micro-blind grooves by EDM on materials with difficult-to-cut/grind surface. The disadvantage of electrode wear in EDM was converted successfully into a critical technology for manufac-turing LLEs and blind microgrooves. The remelting connection layer (RCL) formed on the LLE side wall was investigated, and the RCL was characterized and analyzed using energy dispersive X-ray spectroscopy and X-ray diffraction. The experimental results indicate that the prerequisite for the formation of RCL was dry WEDM, and the uniformity and thickness of RCL were mainly influenced by the removing thick-ness of dry WEDM. In addition, the impact of LLE EDM performance by electrode length and processing depth were also considered, and it was found that the above two parameters had no significant effect on the processing performance. Finally, the LLE was applied to the Ti-6Al-4 V alloy workpiece under the experimental conditions used. The blind multi-microgrooves with a depth of 250 µm and a width of 74 µm were generated, and the crisscross blind microgrooves were prepared. This study demonstrates that the proposed approach can be used to manufacture LLEs with long service life and strong anti-interference ability, and can also be used for succes-sive large-scale manufacturing of deep-narrow blind multi-microgrooves through the EDM technology.