PCM Heat Sinks

A heat sink is a passive heat exchanger that takes heat generated by an electronic or mechanical device and transfers it to a fluid substance such as air or a liquid coolant. From here, the air or liquid is dissipated away from the device to allow the device to operate at its intended temperatures. Despite the name, most heat sinks are actually more like heat exchangers, with the exception of one: the Phase Change Material (PCM) heat sink. In cases where there is nowhere for a device to dissipate heat, the PCM heat sink absorbs it.

Phase change material refers to materials that require large quantities of energy to undergo a phase change (when matter changes from one state to another - i.e. liquid to solid). The energy produced in the transition between solid and liquid phases is known as latent heat of fusion. PCMs with high latent heat of fusion can store a significant amount of heat while maintaining a constant temperature. This property makes PCMs perfect for heat sinks, especially when used for cooling electronic devices. During operation, the thermal energy from a device can be stored in the PCM without the temperature of the device increasing notably. Additionally, while the device is turned off, the PCM can quickly cool so it is ready for the next cycle.

However, PCMs are not without their deficiencies. Because they have low thermal conductivity, the section of the surface in direct contact with a heat source can be totally melted before the heat has evenly spread throughout the entire piece of material. In order to fully utilize a PCM, enhancers such as aluminum or copper ‘fins’ must sometimes be used. These fins will help direct and evenly transfer heat through a PCM. Another issue that must be accounted for is the change in density materials experience during phase change. Depending on what type of PCM is being used, a number of methods are used to compensate for the change in density and volume. In most cases, the PCM size upon installation accounts for this by leaving space at high temperatures.

From temperature stabilization, to short-term thermal storage, and failure protection, PCM heat sinks have many cooling applications in a variety of devices. Beyond all these factors, PCM heat sinks can also reduce system size, cost, maintenance, and power requirements.

At ASAP Purchasing, owned and operated by ASAP Semiconductor, we can help you find PCM heat sinks and all the aircraft electronic components for the aerospace, civil aviation, and defense industries. We’re always available and ready to help you find all the parts and equipment you need, 24/7-365. For a quick and competitive quote, email us at sales@asapsemi.com or call us at 1-714-705-4780.