METHOD FOR ELECTROEROSION DRILLING OF HOLES Russian patent published in 2020 - IPC B23H5/00 B23H5/14 B23H9/14 

FIELD: chemistry.

SUBSTANCE: invention relates to spark-erosion processing, in particular, to erosion-free piercing of holes in hard-to-treat composite layer-fibrous materials containing carbon fibre. Proposed method comprises processing sheet composite laminar-fibrous material containing carbon fibre with electrode-tool connected to current source minus. Cooling working medium in the form of transformer oil is continuously supplied to the processing zone with provision of its turbulent movement along the processed sheet surface, intensive penetration into the interelectrode gap and removal of processing products from it. Providing strictly vertical reciprocal movement of electrode-tool, perpendicular to surface of sheet material, which is processed in following mode: current intensity 0.5–2 A, voltage 100–120 V, pulse action time 150–200 mcs. Surface of sheet material is kept open or closed by tight attachment on it of thin sheet of current-conducting, heat-conducting metal with thickness of 1–1.5 mm in form of solid sheet - strap or sheet-template, having through holes of specified profile, similar to sutured.

EFFECT: technical result is optimized mode of erosion-free erosion of holes, which improves quality of treated surface of composite layer-fibrous material along entire depth of hole and preserves initial state of surface layers of binder.

1 cl, 3 ex, 14 dwg