Heat sinks are devices that transfer heat from a hotter source to a cooler fluid medium, such as air or liquid. They are used in a wide variety of applications, including computers, electronics, and industrial machinery. Here we'll look at how extruded aluminium heatsinks perform compared to other options.
Passive heat sinks
Passive heat sinks rely on natural convection and conduction to transfer heat. They typically have a large surface area and fins to increase the amount of heat that can be dissipated. Passive heat sinks are quiet and reliable, but they are not as effective at cooling as active heat sinks.
Active heat sinks
Active heat sinks use fans or other forced convection methods to transfer heat. They are more effective at cooling than passive heat sinks, but they can be noisy and require more power.
Types of heat sinks by manufacturing process
Heat sinks can be manufactured using a variety of processes, including:
Extruded heat sinks: Extruded heat sinks are made by forcing molten metal through a die to create a desired shape. They are the most common type of heat sink and are the most cost-effective for most applications.
Bonded heat sinks: Bonded heat sinks are made by attaching individual fins to a base plate. This process allows for more complex designs. Although they offer performance improvements over extruded heat sinks they are more expensive.
Skived heat sinks: Skived heat sinks are made by cutting fins from a solid block of metal. This process is used to produce high-performance heat sinks for demanding applications, such as aerospace and military.
Forged heat sinks: Forged heat sinks are made by compressing metal under high pressure. This process produces heat sinks with high strength and density, making them ideal for applications where space is limited as it allows the heatsink itself to form part of the structure.
Types of heat sinks by material
Heat sinks are typically made of aluminium or copper. Aluminium is less expensive than copper, but it is also less thermally conductive. Copper is more expensive than aluminium, but it is also a better conductor of heat.
Types of heat sinks by application
Heat sinks are used in a wide variety of applications, including:
Computers: Heat sinks are used to cool CPUs, GPUs, and other electronic components in computers.
Electronics: Heat sinks are used to cool a variety of electronic components, such as transistors, diodes, and capacitors.
Industrial machinery: Heat sinks are used to cool motors, generators, and other industrial machinery.
Selection of the right heat sink
When selecting a heat sink, it is important to consider the following factors:
Heat dissipation requirements: The heat dissipation requirements of the component being cooled will determine the size and type of heat sink required.
Space limitations: The size and shape of the heat sink must fit within the available space.
Environmental conditions: The heat sink must be able to operate in the environmental conditions of the application.
Budget: Heat sinks can range in price from a few dollars to several hundred dollars.
Conclusion
Heat sinks are essential for cooling a wide variety of components in electronic and industrial applications. There are many different types of heat sinks available, so it is important to select the right one for the specific application.
Although there are heatsinks that provide better performance than extruded aluminium heatsinks, these come with additional costs. In the majority of applications, it is more cost-effective to use extruded aluminium but increase the dimensions of the heatsink rather than opt for copper or more expensive construction methods. It is only where the demands for exceptional performance within very tight dimensions outweigh the cost considerations.
Additional types of heat sinks
In addition to the types of heat sinks listed above, there are a number of other specialised heat sinks available, such as:
Pin fin heat sinks: Pin fin heat sinks are used to cool high-density arrays of electronic components. They are typically made of aluminium or copper and have a large number of small pins that increase the surface area for heat dissipation.
Heat pipes: Heat pipes are used to transfer heat over long distances. They consist of a sealed tube containing a liquid and a wick. The liquid evaporates at the hot end of the heat pipe and condenses at the cold end. This process transfers heat from the hot end to the cold end.
Vapour chambers: Vapour chambers are similar to heat pipes, but they have a much larger surface area. This makes them ideal for cooling high-performance electronic components.
Emerging heat sink technologies
A number of new heat sink technologies are currently in development, including:
Microchannel heat sinks: Microchannel heat sinks are made using microfabrication techniques. They have very small channels that allow for very efficient heat dissipation.
Graphene heat sinks: Graphene is a new material with excellent thermal conductivity. Graphene heat sinks are still in the early stages of development, but they have the potential to be even more efficient than traditional heat sinks.
Conclusion
Heat sinks are essential for cooling a wide variety of components in electronic and industrial applications. There are many different types of heat sinks available, and new technologies are constantly being developed. When selecting a heat sink, it is important to consider the heat dissipation requirements of the component being cooled, the space limitations of the application, and the budget.
