Aluminum PCBs

Rush PCB UK makes various types of printed circuit boards. One among them is the Aluminum PCB. As the name suggests, these are boards with a base of aluminum on which circuit layers form a covering. The aluminum plate may also be an alloy plate, with a combination of silumin, aluminum, and magnesium.

Offering several advantages like high electrical insulation, great machining performance, aluminum PCBs also exhibit great thermal performance. In comparison with other printed circuit boards, aluminum PCBs differ in many important ways.

The main advantage in using aluminum PCBs is their superior ability to manage thermal issues. The presence of aluminum in the board substantially improves heat transfer from essential components generating heat while operating. This precludes the use of a separate heat sink for thermal management.

The second advantage in using aluminum PCBs is their higher mechanical strength and durability. Compared to boards made of ceramic and fiberglass base, aluminum PCBs are significantly stronger and more durable. This improves the life-span of any product using aluminum boards.

The structure of aluminum PCBs is similar to that of FR-4 circuit boards, only they use different materials. The base material is a layer of sheet aluminum, with a circuit layer made of copper foil, and a thin dielectric layer separating the two.

An aluminum substrate forms the base layer of the PCB. Being made of aluminum metal, the base has a high thermal conductivity. A surface finish on the substrate prevents the exterior of the layer from acquiring scratches and scrapes.

Dielectric Insulating Layer

With a thickness between 50 and 200 microns, the dielectric layer on the aluminum base is thermally conductive, but electrically insulating. Its low thermal resistance helps conduct heat away from any hot component and transfer it to the aluminum base for dissipation.

Copper Foil Layer

The copper layer forms the tracks of the circuit, interconnecting various components so they can perform their electrical functions. Although this is similar to the copper layer in regular FR-4 boards, aluminum PCBs use a thicker copper layer. This allows the copper traces to carry higher current.

Solder Mask

A solder mask covers the circuits on the copper layer, protecting the copper surfaces from oxidizing. Although this is similar to the solder mask on FR-4 boards, the extra thickness of the copper layer makes printing the solder mask a difficult process.

Components

Aluminum PCBs mostly use SMD components soldered on the copper foil layer circuits. This allows the base to act as a heat sink for any component generating heat while operating. Although this makes the aluminum PCBs single-sided, other complex structures can have multiple layers, with through holes connecting the circuits through the aluminum base layer.

Uses of Aluminum PCBs

Aluminum PCBs are useful in high-power applications that require fast dissipation of heat to allow proper functioning. Examples of such applications are domestic, traffic, and automotive lighting using high-illumination LEDs. Although LEDs are highly efficient when producing illumination, at high powers, they must dissipate some heat that, if not removed, could shorten their life. The presence of aluminum in the base of the PCB helps to remove the heat from the LEDs, allowing them to operate at full capacity without undue failures.

Conclusion

For any type of aluminum PCB, please contact Rush PCB UK to get an instant quote and fast turnover. We make all types of aluminum PCBs, single-sided, double-sided, and multilayered.