Projections show that the global carbon fiber market will grow at a cagr of 12.9% between 2022 and 2032.
It’s becoming very popular all over the world and many companies are replacing other materials with it. Aluminum is very widely used, but that doesn’t necessarily mean it’s better. Both have advantages that make them useful in different industries, so which one should you be using?
Keep reading for a side-by-side comparison of aluminum vs. carbon fiber.
Light materials are ideal for various applications. Keeping the weight of vehicles down, for example, can help improve speed and fuel efficiency.
One of the well-known benefits of carbon fiber is its weight. It has a density ranging from 1.75-1.93g/cm³.
In general, aluminum weighs twice this for the same volume of material. This is still fairly light when compared to other similar materials, but carbon fiber is superior in this aspect.
Strength is a measurement of how much load they can take before bending or failing. When comparing the two weight-for-weight, carbon fiber has a strength of around 2 to 5 times more than aluminum.
At the Same Weight
If you had a sheet of each material with the same area and weight, the carbon fiber would be almost twice as thick as the aluminum. Many applications are dependent on weight, so you could choose between the two materials, and get much more strength from a carbon fiber part that weighs the same as an aluminum part.
At the Same Thickness
If thickness was a more important factor for an application, carbon fiber would still be the better choice. This is common when engineers are replacing an aluminum part with a carbon fiber part, as it will need to fit correctly wherever it is being used.
Aluminum and carbon fiber parts can be manufactured to the same dimensions. In this case, the carbon fiber part will be around 60% stronger, while still weighing about half as much. Carbon fiber parts also return to their original shape after releasing a load, whereas aluminum will deform permanently.
Aluminum has a much higher heat conductivity than carbon fiber, as heat will transfer through it about 40 times faster. The heat expansion of aluminum is also about 6 times higher than that of carbon fiber.
Both have a reasonable heat resistance up to about 400°F (~200°C). A key advantage of carbon fiber here is that it doesn’t melt, whereas aluminum has a melting point of about 1120°F (~660°C).
The price can vary depending on the grade of materials, but aerospace-grade carbon fiber can cost around $90/kg. This grade isn’t necessary for all applications, but it’s the best type that’s widely available.
This is one area where aluminum has a major advantage. It typically costs about 45 times less than carbon fiber per kg. As such, it can be much better when the cost is more important than physical characteristics.
Aluminum vs. Carbon Fiber – Which Is Best?
When comparing aluminum vs. carbon fiber, it’s clear that the physical properties of carbon fiber are superior. It’s stronger, lighter, and has better heat resistance.
Aluminum is far cheaper, hence why it’s often used for things like beverage cans, cooking utensils, and food-processing equipment. Industries like aerospace and the medical field often choose carbon fiber due to its many advantages.
If you need composite carbon fiber parts, SMI Composites is a leading producer. Visit our capabilities page today to see what we can offer.