1. Introduction
When faced with the choice of Copper vs Aluminium Heatsink for a particular design project, many engineers first consider thermal performance…
But as you will see below, several other factors also influence material selection for heat sinks.
Weight, raw material cost, manufacturability, corrosion resistance, and application-specific requirements can all play a factor.
Thermal conductivity is higher in copper.
Aluminium, on the other hand, provides lighter weight and easier manufacturability.
Because of these differences, there is no clear answer as to which material is better.
However, copper tends to be the preferred choice in high heat flux applications.
Aluminium tends to work well in general industrial and electronic cooling applications.
So deciding which material to use really depends on the requirements of the thermal design as a whole.
Factors to consider include:
- Thermal conductivity
- Density
- Material Cost
- Machinability
- Extrusion performance
- Corrosion resistance
- Heat spreading
- Structural requirements
See 【 What Is a Heat Sink 】for background information on heat sinks.
2. Copper Heatsink
Excellent thermal conductivity also allows copper heatsinks to spread heat away from high heat flux sources.
Copper also excels at heat spreading.
This can be particularly advantageous when heat loads are transferred to the heat sink by way of a small contact area.
High power semiconductor devices are one example.
These devices can produce very dense thermal loads. Since copper excels at spreading heat, it can help transfer heat to a larger cooling area.
Copper has a high density relative to aluminium.
As a result, copper heatsinks are generally much heavier than aluminium ones.
Copper is also more expensive than aluminium for most applications.
That being said, copper is commonly used in applications where the thermal requirements justify the additional material cost.
Some of the manufacturing processes used for copper heatsinks include:
- CNC machining
- Skiving
- Forging
- Extrusion
- Bonding
- Composite construction
See 【 Copper Heat Sink 】for further details on copper heatsinks.
3. Aluminium Heatsink
Aluminium continues to be a very popular choice of material for heatsinks.
It offers a good compromise between thermal performance and weight.
This makes aluminium ideal for many commercial and industrial cooling applications.
Aluminium heatsinks also take advantage of aluminium’s excellent extrusion properties.
Complex fin designs can be made using aluminium extrusion processes. For this reason, extrusion is often used for high volume production of aluminium heatsinks.
Two common aluminium alloys are 6063 and 6061.
60 – 63 provides excellent extrusion characteristics.
60 – 61 has higher mechanical strength characteristics. Engineers can choose which alloy to use based on their specific application needs.
Corrosion resistance is good with aluminium.
In addition, the low density makes it easier to handle and install compared to copper.
See 【 Aluminium Heat Sink Material 】for more information on aluminium as a heatsink material.
4. Copper vs Aluminium Heatsink Comparison
Below is a table comparing copper and aluminium heatsinks.
Property Copper Heatsink Aluminium Heatsink
Thermal Conductivity Higher Lower
Density Higher Much lower
Weight Heavy Lightweight
Material Cost Higher Lower
Heat Spreading Excellent Good
Extrusion Limited Excellent
Machining Good Excellent
Corrosion Resistance Good Good
Production Cost Higher Lower
Typical Use High heat flux General cooling
As you can see, copper provides better thermal conductivity.
Aluminium is lighter and less expensive however.
It all depends on your application.
5. Thermal Conductivity Comparison
Thermal conductivity is a measure of a material’s ability to conduct heat.
Copper generally has a higher thermal conductivity than aluminium.
The thermal conductivity of copper is approximately 400 W/ m·K.
Aluminium’s thermal conductivity is typically around 200-235 W/ m·K.
Exact numbers will vary by alloy, and material condition.
Consult the material specification when doing thermal calculations for your project.
The higher thermal conductivity of copper gives it one advantage over aluminium.
Copper heatsinks can spread heat quickly away from high heat flux sources.
As such, copper heatsinks are ideal to use with high power components.
Remember though, thermal conductivity isn’t the only factor that determines heatsink performance.
Fin geometries are equally important.
Also consider airflow, total surface area, thermal interface material, and mounting pressure.
A well designed aluminium heatsink can outperform a poorly designed copper heatsink.
6. Weight and Density
Weight is another area where copper and aluminium differ significantly.
Copper has a density of around 8.96 g/ cm³.
Aluminium’s density is about 2.70 g/ cm³.
This means copper is over three times as dense as aluminium.
This is a significant difference that can matter in some applications.
Mobile equipment is one example where weight matters.
Aluminium would be the preferable material for these types of applications.
Transportation applications can also benefit from lightweight components.
Industrial applications that are not mobile can typically use copper since weight is less of a concern.
7. Cost Comparison
Cost is always a concern when it comes to picking materials for a project.
Right now, copper costs more than aluminium.
Keep in mind that material prices go up and down based on market conditions.
Copper has typically been the more expensive material when comparing the two.
That being said, aluminium heatsinks are especially attractive when designing large heatsinks.
This will become apparent when you are manufacturing heatsinks in high volumes.
A large extruded aluminium heat sink can provide a lot of cooling area while keeping material costs relatively low.
Copper makes more sense when using it will provide clear thermal benefits.
Consider total system cost, not just material costs.
8. Heat Dissipation Performance
Heat dissipating ability of a heatsink is affected by many things.
The material of the heat sink is only one factor to consider.
Other characteristics include:
- Fin height
- Fin thickness
- Fin spacing
- Base thickness
- Air velocity
- Contact resistance
- Ambient temperature
- Thermal interface material
Keep these things in mind when selecting a material for your heatsink.
Copper has the ability to spread heat better than aluminium.
Aluminium on the other hand can have a larger fin surface area due to extrusion.
This allows aluminium to hit a nice sweet spot of good conductivity and large surface area.
Adding forced airflow into the mix can change things as well.
By adding a fan, you can force more air across the fins.
This allows you to increase heat transfer without using copper.
9. Manufacturing and Machining
Material properties also play a role in how heatsinks can be manufactured and processed.
Aluminium Extrusion
Aluminium has excellent extrusion capabilities.
As a result, heatsink manufacturers can produce complex heatsink profiles in an efficient manner.
The extrusion process allows for:
- Straight fins
- Pin fins
- High-density fins
- Custom mounting brackets
- Integrated channels
Check out 【Heat Sink Extrusion】 and 【Heatsink Extrusion Profiles】.
Copper Machining
Copper allows for precise machining of components and mounts.
On the downside, copper material costs will raise manufacturing costs.
As a result, manufacturers typically reserve copper heatsinks for special applications.
Skiving
Skiving allows manufacturers to shave extremely thin and dense fins from blocks of metal.
As a result, skived heatsinks are ideal for high performance heat dissipation applications.
CNC Machining
CNC machining allows for intricate mounting holes and structures to be created.
As a result, CNC machining can be performed on aluminium heatsinks or copper heatsinks.
See 【Heat Sink CNC Machining】.
10. Copper vs Aluminium Heatsink Applications
Heat sink applications can vary across industries and even sectors.
Industrial Electronics
Industrial control systems and components typically require reliable thermal management solutions.
As a result, aluminium heatsinks remain a go-to solution for industrial applications.
Power Electronics
Power semiconductors and modules can produce massive amounts of heat.
As a result, copper heatsinks are sometimes used in these applications to manage higher heat flux.
That being said, aluminium heatsinks are still very common in power electronics.
LED Lighting
LED lights and lighting arrays require heat to be quickly removed from the semiconductor.
As a result, aluminium heatsinks are very common in LED light applications.
Aluminium’s lightweight properties also benefit LED lighting design.
Data Centers
Data center CPUs such as AI servers and HPC systems produce a lot of heat.
As a result, thermal engineers will often use a combination of heat management technologies.
Copper can be used to spread heat effectively.
Aluminium provides lightweight fin stacks.
As a result, thermal engineers can craft hybrid solutions to meet unique cooling needs.
See 【Vapor Chamber for Data Center Cooling】.
EV Power Electronics
Power modules, inverters, and onboard chargers are all used within electric vehicles.
As a result, thermal management is still very important within the EV industry.
Aluminium allows for weight to be saved.
Copper can handle more intense heat loads in smaller areas.
As a result, both materials can be used by engineers depending on the system design.
CPU and GPU Cooling
CPUs and GPUs can produce very high heat output within a small area.
As a result, copper allows for heat to be spread effectively.
However, many CPU and GPU coolers use copper bases with aluminium fins.
See 【Vapor Chamber for GPU Cooling】 to learn about another high-performance cooling solution.
11. How to Choose Between Copper and Aluminium
Keep the following questions in mind when choosing between copper and aluminium heatsinks.
Choose Copper When:
- Heat flux is extremely high.
- Heat spreading is important.
- Weight is not a primary concern.
- Higher costs aren’t an issue.
- The part has a small surface contact area.
As a result, copper heatsinks are well suited for demanding thermal applications.
Choose Aluminium When:
- Weight is a major factor.
- Production volume will be high.
- Keeping costs low is important.
- Extrusion is your preferred design method.
- Thermal loads are only moderate.
As a result, aluminium heatsinks are typically used in most electronic products.
Choose a Hybrid Design When:
- Your heat source needs good heat spreading.
- You want your cooling fins to be lightweight.
- You need a balance of performance from your heatsink.
- Your design would benefit from lower copper usage.
As a result, copper and aluminium can be used together to provide the best of both worlds.
12. Hybrid Copper-Aluminium Heatsinks
Hybrid heatsinks use copper and aluminium in a single cooling solution.
One popular design starts with a copper heat spreader base.
Aluminium fins attach to the copper heat spreader.
As a result, the copper base can spread heat quickly.
And aluminium fins provide high surface area without too much weight.
This gives thermal engineers a way to utilize both copper and aluminium.
Hybrid copper heatsinks can also use less copper.
As a result, the overall weight and cost of the heatsink can be reduced.
There are many methods to securely join copper and aluminium heatsinks.
These methods can include:
- Brazing
- Soldering
- Mechanical bonding methods
- Press fitting
- Other advanced joining solutions
The correct joining method depends on your product design.
13. Heatsink Manufacturing Equipment
Manufacturing heatsinks from scratch will require a variety of equipment.
Here is a list of common heatsink manufacturing equipment:
- Aluminium extrusion machine
- Heatsink cutting machine
- 【Heat Sink Fin Machine】
- CNC machining equipment
- Surface treatment machine
- Heat pipe assembly machine
- 【Heat Sink Assembly Machine】
- Inspection equipment
As a result, manufacturers can establish full heatsink production workflows.
Automated equipment can ensure consistency for high-volume production.
You can learn more about building a full 【Heat Sink Manufacturing Line】.
Advanced thermal cooling solutions can even make use of heat pipes or vapor chambers.
As a result, manufacturers have the opportunity to create custom thermal assemblies.
14. Why Choose Bangwin Machine?
Bangwin Machine is a thermal manufacturing solution provider that offers equipment and customized production options.
The company specializes in manufacturing equipment for:
- Heat sinks
- Heat pipes
- Vapor chambers
- Complete thermal assemblies
As a result, Bangwin Machine can assist manufacturers that make a variety of thermal management products.
Whether it be just heatsinks or entire thermal assemblies, Bangwin Machine has equipment that can cover most production stages.
These stages can include but are not limited to:
- Fin processing machinery
- Extrusion related manufacturing
- CNC machining
- Heat pipe assembly machines
- Vapor chamber production
- Automated thermal assembly equipment
Furthermore, Bangwin Machine can tailor equipment to your unique production needs.
As a result, you can build your production line around your product designs and desired output volumes.
Visit Bangwin Machine’s thermal machinery website to learn more about their:
Bangwin Machine Thermal Machinery
Home
Their website offers details about their thermal machinery and custom production options.
16. FAQ
l Is copper or aluminum better for a heatsink?
Copper has better thermal conductivity than aluminium.
Aluminium provides significant savings on weight and costs.
As a result, there is no definite answer.
l Which heatsink material conducts heat better?
Copper heatsinks conduct heat better than aluminium heatsinks.
Don’t forget that fin design and airflow also play a huge role in heatsink performance.
As a result, thermal conductivity doesn’t define heatsink performance.
l Why do people use aluminium heatsinks?
Aluminium provides great thermal performance at low weight and low cost.
Another reason is that aluminium allows for efficient extrusion manufacturing.
As a result, aluminium is ideal for large scale heatsink production.
l Why are copper heatsinks so expensive?
Copper is more expensive than aluminium and weighs more.
Certain copper manufacturing methods cost more as well.
As a result, copper heatsinks will typically be more expensive than aluminium heatsinks.
l Can aluminium and copper be used together?
Yes they can.
By combining copper heat spreaders with aluminium fins, you can make a hybrid heatsink.
As a result, you get the heat spreading performance of copper with the low weight of aluminium.
l Which heatsink is best for GPU?
This will depend on your GPU and its power levels.
Gaming GPUs typically use multiple thermal solutions.
As a result, copper gives you effective heat spreading.
Aluminium provides light weight fins and structures.
l Which material should I use for industrial heatsinks?
Aluminium heatsinks can be used for most industrial applications.
Copper can be used when your components have very high heat flux.
As a result, evaluate the thermal load and installation environment.
l Do you sell equipment for aluminium and copper heatsinks?
Yes we do.
Bangwin Machine sells custom thermal manufacturing equipment.
Our customers can use our equipment to make heatsinks, heat pipes, vapor chambers, and thermal assemblies.
17. Conclusion
There are many factors to consider when comparing Copper vs Aluminium Heatsinks.
Copper offers greater thermal conductivity and heat spreading capabilities.
Aluminium offers lighter weight, lower cost, and can be extruded into complex shapes.
That is why aluminium heatsinks are so common in industry.
Copper heatsinks are better when your application needs the best heat spreading possible.
However, you can always use both copper and aluminium to create a hybrid heatsink.
Take heat load, airflow, weight constraints, budget, desired manufacturing method, and available space into consideration when choosing your heatsink.
As technologies like AI computing, power electronics, industrial automation, and data centers expand, they will create more demand for efficient thermal management.
As a result, thermal management companies will need reliable machinery to produce efficient heatsinks.
Bangwin Machine is here to provide those manufacturers with thermal machinery for heatsinks, heat pipes, vapor chambers, and other thermal components.
Visit Bangwin Machine’s thermal machinery website at:
Bangwin Machine Thermal Machinery
