PCB aluminum substrate is also called aluminum cladding, aluminum pcb, metal coated printed circuit board, thermal conductive PCB, etc. the advantage of PCB aluminum substrate is that the heat dissipation is obviously better than the standard FR-4 structure. The dielectric used is usually 5 to 10 times the thermal conductivity of conventional epoxy glass, and the heat transfer index of one tenth of the thickness is more efficient than the traditional rigid pcb.
Aluminum PCB types：
1. Flexible aluminum substrate
One of the latest developments in our materials is flexible dielectrics. These materials can provide excellent electrical insulation, flexibility and thermal conductivity. When applied to flexible aluminum materials such as 5754 or similar, products can be formed to achieve various shapes and angles, which can eliminate expensive fixtures, cables and connectors. Although these materials are flexible, they are designed to bend into place and remain in place.
2. Mixed aluminum substrate
In the "hybrid" structure, the "sub components" of non-thermal substances are treated independently and then bonded to the aluminum substrate with thermal materials. The most common structure is a 2-layer or 4-layer subassembly made of traditional FR-4. Bonding this layer to an aluminum substrate with thermoelectric medium can help heat dissipation, improve rigidity and act as a shield. Other benefits include:
1. Lower cost than building all heat conducting materials.
2. Provide better thermal performance than standard FR-4 products.
3. Expensive radiator assembly and related steps can be eliminated.
4. It can be used in RF applications requiring RF loss characteristics of PTFE surface layer.
5. The use of component windows in aluminum to accommodate through-hole components allows connectors and cables to pass connectors through the substrate while welding fillets to produce a seal without the need for special gaskets or other expensive adapters.
3. Multilayer aluminum substrate
In the high-performance power supply market, multi-layer PCB is made of multi-layer thermal conductive dielectrics. These structures have one or more layers of circuits embedded in the dielectric, and blind holes are used as thermal vias or signal paths. Although single-layer designs are more expensive and less efficient to transfer heat, they provide a simple and effective heat dissipation solution for more complex designs.
4. Through hole aluminum substrate
In the most complex structures, a layer of aluminum can form the "core" of multi-layer thermal structure. Before lamination, aluminum is plated and filled with dielectric in advance. The thermal material or sub component can be laminated to both sides of the aluminum using a thermal bonding material. Once laminated, the finished components are similar to traditional multilayer aluminum substrates through drilling. Electroplated through holes pass through gaps in aluminum to maintain electrical insulation. Alternatively, the copper core may allow direct electrical connection and insulated through holes.
