Solving Tension Control Challenges for Ultra-Thin Copper Foil (<3μm) in R2R Manufacturing

Solving Tension Control Challenges for Ultra-Thin Copper Foil (<3μm) in Roll-to-Roll (R2R) Manufacturing

(±0.1N Precision Full-Process Solution)

I. Core Challenges of Ultra-Thin Foil

II. Four-Dimensional Tension Control

1. Material Enhancement

• Composite Reinforcement:

  Cu foil(3μm) + Polyimide carrier(12μm) + Nano-adhesive(0.5μm)  

  3x higher tensile strength (150MPa)

• Edge Reinforcement:

  Position	Treatment	Width
  Foil edges	Laser-deposited Ni alloy	1.0mm
  Seam zone	Plasma-enhanced coating	3.0mm

2. Precision Mechanical System

• Air-Floatation Rollers:

  • Surface roughness: Ra≤0.05μm

  • Coaxiality: ≤±1μm/300mm

  • Temp control: ±0.5℃ (Peltier cooling)

• Zoned Tension Control:

  Zone	Target Tension(N)	Precision
  Unwinding	0.8-1.2	±0.05N
  Process Core	1.5-1.8	±0.03N
  Rewinding	2.0-2.5	±0.08N

3. Multi-Sensor Monitoring

Sensor Specs:

• Tension: Fiber Bragg Grating (FBG), ±0.01N resolution

• Thickness: Beta-ray gauge, ±0.05μm accuracy

4. Intelligent Control Algorithm

• Adaptive PID:
  $u(t)=K_{p}e(t)+K_i{\int }_0^{t}e(\tau )d\tau +K_d\frac{de(t)}{dt}+\alpha \cdot \mathrm{\Delta }T$
  *Temp comp coefficient α=0.15N/℃*

• Digital Twin Prediction:

  python

  def digital_twin_SIMulation(speed, temp, thickness):
  risk = lstm_model.predict([[speed, temp, thickness]])
  return max_tension = 2.5 - 0.7 * risk # Safety margin

III. Key Process Parameters

IV. Performance Comparison (3μm Cu Foil)

Validation:

1. Tension curve: Montalvo Tension Monitor

2. Deformation: Keyence laser displacement sensor

3. Microstructure: SEM grain orientation (<5° deviation)

V. Emergency Mechanisms

1. Breakage Prediction:

   • Acoustic emission sensor (>200kHz micro-crack detection)

   • Auto slowdown in <50ms

2. Wrinkle Elimination:

   • Dynamic roller wrap angle: 30°±2°

   • Localized IR heating: 150℃/0.5s