1. Core technological advantages

1. Purity guarantee

Using electrolytic nickel plate as the base material directly avoids the introduction of impurities through traditional melting and casting, resulting in an improvement of conductivity by over 7%.

2. Organizational refinement

The forging and rolling process controls the grain size to be within 5–10μm, significantly enhancing the toughness of the wire material compared to the melting and casting method.

3. Limit diameter

It can achieve continuous production of ultra-fine wires of 0.025mm, breaking through the wire breakage bottleneck of traditional drawing processes.

II. Key process steps

1. Electrolytic nickel pretreatment

Surface treatment: mechanical polishing + acid pickling (H₂SO₄₃=3:1) to remove oxide scale, with Ra≤0.8μm.

Blank cutting: Cut the nickel plate into strips with a width of 10–20mm to reduce stress concentration during subsequent rolling.

2. Multi-stage forging and rolling forming

Intermediate annealing: After precision rolling, conduct vacuum annealing at 850℃ for 30 minutes to restore plasticity.

3. Precision drawing and sizing

Mold selection: diamond polycrystalline mold (hole diameter tolerance ±0.001mm).

Drawing parameters:

Speed: 0.5–2 m/min (speed decreases as wire diameter decreases)

Pass deformation: 8–12%

Tension control: ≤50N (to prevent wire breakage).

III. Key points of quality control

Defect prevention: Eddy current flaw detection for microcracks, and electrolytic polishing to eliminate surface stress concentration points.

Summary: Reducing the work-hardened layer through "rolling instead of drawing" and eliminating grain boundary defects through vacuum annealing have become the mainstream preparation methods for ultra-fine high-conductivity nickel wires.