Aluminium backed PCBs - what are the benefits?

Published Friday 23rd November, 2018

Printed circuit boards have to be designed and manufactured for highly specialised purposes, and in some situations, an aluminium backed PCB may be the best solution.

Let's take a look at why and when aluminium is used over the more common fibreglass in the manufacturing of circuit boards, to help you decide if it’s the best solution for your PCB designs.

The advantages of aluminium

Aluminium is used in PCB design as a thermal dissipater in electronic devices that generate a lot of heat because of their high power output.

Its ability to draw heat away from the valuable and delicate components of a circuit board is around ten times that of standard fibreglass used in most PCBs, but that's not the only advantage...

– Aluminium is non-toxic, easy to work with and readily recyclable, making it a great solution from an environmental point of view.

– Aluminium has an incredible strength-to-weight ratio, making it an ideal material to use in high-stress situations because it can cope with greater levels of mechanical pressure while maintaining its mechanical stability. In fact, it’s perfect for any situation that requires a strong and lightweight solution - high-stress or not.

– It's relatively cheap, although there’s some controversy surrounding President Trump's 10% import tariff on aluminium from the EU, Canada and Mexico – so we recommend being aware of this before deciding if it’s the best material for you.

– Aluminium’s strength and ease of use makes it a more durable material during the manufacturing process because it resists breakage with much more readiness than fibreglass or ceramic. It could be argued that the additional cost of using aluminium can be offset in certain circumstances by this intrinsic ability to stand up to the stresses and strains of manufacturing, testing and day-to-day use.

– Aluminium's ability to resist thermal expansion makes it perfect for PCB designs that require very tight degrees of tolerance to function effectively over a lifetime’s use. The ability to place components much closer together on the board without fear of overheating offers the technician many more options during the design process.

Industry uses for aluminium backed PCBs

Now that we've established the benefits of an aluminium backed PCB, we can take a look at the applications they’re most readily applied to in modern electronics:

– LED lighting as LED takes over from conventional bulbs, we’re seeing a greater need for PCBs able to handle the heat generated by large numbers of small bulbs in a confined space. Aluminium is by far the best solution here, and is used in everything from traffic lights and car headlamps to commercial and domestic lighting.

– Power supplies aluminium allows manufacturers to design simpler PCBs because its ability to dissipate heat effectively solves many of the problems a contained and constant heat source presents.

– Power transmission systems again, aluminium's excellent thermal dissipation is ideal for these high-stress and temperature environments.

As you can see, aluminium backed PCBs are becoming a more common solution in a multitude of industries and applications - to they may be worth considering for your next project.