Machining method for cutting small round hole with inner diameter of 0.2 mm by slow wire feeding

The invention discloses a machining method for cutting a small round hole with an inner diameter of 0.2 mm by slow wire feeding. The machining method comprises the steps of: 1, manufacturing a mold: 2, selecting a plate A (4) and a plate B (5); 3, forming a plurality of semicircular grooves A (6) with allowances in the right end face of the plate A (4) along the length direction thereof, and a plurality of semicircular grooves B (7) with allowances in the left end face of the plate B (5) along the length direction thereof; 5, placing one end of the spliced plate A and plate B into a rectangular groove (2); and 6, penetrating a steel wire of a wire cutting machine into an area defined by the semi-circular grooves A (6) and the semi-circular grooves B (7), starting wire cutting after the steel wire is installed in place, enabling the steel wire to move in a circular mode with the diameter of 0.2 mm, cutting off the remaining allowances on the plate A and the plate B by the steel wire inthe moving process, and f