Effection of Copper price fluctuation on Copper pet tape
Copper metal price decreased by 590 CNY/ton on October 13 ,2026. The corresponding price adjustments for copper-polyester composite tape are as follows:
- CU18+PET25: price reduction of 480 CNY/ton
- CU15+PET23: price reduction of 470 CNY/ton
- CU20+PET20: price reduction of 500 CNY/ton
- CU18+PET12: price reduction of 530 CNY/ton
Why Cu-PET tape cannot be replaced by Al-PET tape in cables
Al-PET tape is cheaper, but direct substitution is not allowed for cables specified with copper-polyester (Cu-PET) tape, mainly for the following reasons:
Short-circuit current carrying capacity (most critical)
Copper has much higher conductivity than aluminium. Cu-PET tape acts as a return path for fault short-circuit current. When cable insulation breaks down, the copper layer can safely discharge short-circuit current to ground without instant melting. Aluminium has higher resistivity. The thin aluminium layer of Al-PET tape can only withstand very limited short-circuit current. It will melt quickly under fault current, resulting in total shield failure and potential safety hazards.
Shielding performance & transfer impedance
Cu-PET tape delivers excellent shielding for both low-frequency and high-frequency interference with low transfer impedance. It suits analogue signals, instrumentation cables and precision control cables. Al-PET tape works well for high-frequency shielding, but performs poorly against low-frequency magnetic fields. Continuous grounding relies on an additional copper drain wire; without it, shielding will be unstable.
Termination and long-term reliability
Copper can be soldered or crimped directly with stable contact resistance. Aluminium forms an insulating oxide film on its surface and cannot be soldered easily. When aluminium contacts copper terminals in humid environments, galvanic corrosion occurs. The aluminium layer degrades gradually, contact resistance rises and shielding performance drops over time.
Mechanical property
Aluminium foil is brittle. Micro-cracks or breaks may appear during bending, pulling or compression, which breaks the shielding continuity. Copper foil has better toughness and resistance to tearing and repeated bending.
Specification & contract requirement
Cu-PET tape and Al-PET tape are defined as separate materials in industry standards. If the drawing or technical agreement specifies Cu-PET shield, switching to Al-PET tape counts as material change. It will fail type tests and site acceptance unless the customer approves the change in writing.We offer professional solutions of copper-polyester composite tape for cable use.
More about the copper polyester tape (CU+PET) refer site