Two of the most commonly used non-ferrous metals in today’s industries are copper and aluminium. Both are highly conductive, have a relatively low density relative to many other metals and are easily recyclable. However, they have differing physical characteristics, price, weight, durability, and uses.
When it comes to the decision between copper and aluminum, manufacturers, engineers, fabricators and metal buyers are not just picking the less expensive option. The selection depends on the electrical, mechanical, thermal, weight and environmental requirements of the application.
In this guide, we’ll take a look at the differences between copper and aluminum, and discuss the applications of each metal.
What is the difference between the copper and aluminum?
Both copper and aluminum are very useful metals in industry, but they have very different physical properties.
Copper has a relatively high density, and it is well known for its excellent electrical and thermal conductivity. The other material, aluminium, is much lighter and provides a desirable combination of conductivity, corrosion resistance and cost.
Copper: Properties and Advantages
Copper has been used for thousands of years, but its importance has increased dramatically with the growth of electrical and electronic technologies.
Copper’s biggest benefit is its electrical conductivity. This is especially useful for electrical wiring, cables, motors, transformers, generators, busbars and many other electrical parts.
Copper is also a good conductor of heat and can be used in heat exchangers, cooling systems, and other applications that require efficient heat dissipation.
Copper has the following significant benefits:
- Excellent electrical conductivity
- High thermal conductivity
- Good corrosion resistance
- Excellent ductility
- Good machinability
- Strong recyclability
- High performance in a variety of industrial applications.
Copper can also be manufactured and provided in several forms such as copper ingots, copper bars, copper rods, copper sheets, copper tubes and copper wires.
The properties and advantages of Aluminum.
The metal aluminium is one of the most common metals used in the world, and this is due to its low density and versatility.
The low weight is one of the most important properties of aluminium. Aluminium has about one-third the density of copper and this can be very beneficial when weight is a critical factor.
Aluminium also forms a thin layer of oxide when exposed to the air, which provides some protection against further corrosion under many circumstances.
The benefits of using aluminium are:
- Low density
- High strength-to-weight potential
- Good electrical conductivity
- Good thermal conductivity
- Corrosion resistance
- Excellent formability
- High recyclability
Such properties make aluminium a very useful metal in transportation, building, electrical, packaging and manufacturing applications.
Copper vs Aluminium for Electrical Applications
One of the most significant difference between the two metals is electrical conductivity.
Usually, copper has higher electrical conductivity than aluminium. For a given design and operating conditions, a copper conductor will have a smaller cross sectional area than an aluminium conductor to carry the same amount of electrical current.
But when weight is a critical factor, aluminium’s lower density may be appealing.
Engineers might therefore need to take into account both conductivity and weight for large electrical systems, instead of just conductivity.
Copper is commonly found in:
- Electrical wiring
- Motors
- Transformers
- Switchgear
- Busbars
- Generators
- Electrical connectors
Aluminium is also used extensively in electrical transmission and distribution, especially when weight is a factor of logistical or engineering benefit.
Depending on the voltage, current, conductor size, installation conditions, connection design and applicable standards, the appropriate material is determined.
Which is heavier, copper or aluminum?
Copper is much heavier than aluminium.
This is especially significant when a large amount of metal is needed.
For instance, two components will have the same physical volume, but the copper component will be much heavier than the aluminium component.
This can make aluminium appealing for use in:
- Aircraft
- Automobiles
- Transportation equipment
- Overhead electrical lines
- Lightweight structures
- Portable equipment
But weight is not the only factor. Copper can be selected over other materials because of its high conductivity, compactness, durability or other characteristics, even though its density is higher.
A comparison of the cost of copper and aluminium.
It is also important to take into account cost.
Copper and aluminium market prices are subject to fluctuations over time, depending on the global demand and supply, production, inventories, energy costs, economic conditions, and other market factors.
The price of aluminium is generally lower per kg than copper, although this can vary depending on market conditions and product specifications.
But a comparison of the price per kg alone may not be accurate.
A buyer needs to take into account the quantity of material needed to obtain the desired performance.
For instance, a component of aluminium could be a larger size than a copper component to give the same electrical performance. On the other hand, the lower density of aluminium can offer considerable weight saving.
So, it is best to compare costs per required performance, not just cost per kilogram.
Copper vs Aluminium in Construction
Copper is a material that is used in construction.Copper is a material that is used in construction.
These two metals are both of significance in the construction industry.
Copper is widely used in electrical systems, plumbing, roofing, architectural applications, and specialized uses.
Aluminium is used extensively for:
- Window and door frames
- Roofing
- Cladding
- Structural components
- Building systems
- Electrical applications
Aluminium has a low weight and is highly resistant to corrosion, which is why it is often used for many architectural purposes.
Copper may be desirable for its long-lasting appearance, electrical conductivity, thermal conductivity, and durability.
What metal is more resistant to corrosion?
Copper and aluminium both possess some useful corrosion resistance properties but in different ways.
Aluminium immediately oxidises to form a thin layer of oxide. This layer may act as a metal protection layer.
Over time, copper forms its own surface products, which may alter the copper’s appearance and offer some protection.
Both materials will perform well in a specific environment, but not in all environments.
Factors such as:
- Moisture
- Temperature
- Salt exposure
- Chemicals Contact with other metals
- Surface treatment
- Installation conditions
can all influence performance.
Therefore, when selecting materials it is important to take into account the environment in which the material is going to be used and not just that one metal is better than another.
Copper vs Aluminium for Heat Transfer
Copper and aluminium are good conductors of heat.
Copper is typically used in applications where efficient heat transfer is important, as it has a higher thermal conductivity.
Aluminium, on the other hand, has a desirable thermal conductivity and is much lighter.
This renders both metals as useful in heat exchangers, cooling systems, radiators and other thermal-management applications.
It is dependent on the desired thermal performance, weight, cost, manufacturing process and operating environment.
Copper and Aluminium are both vital to the industry, but why?
The choice is often incorrectly pitted as copper versus aluminium, but both are used in today’s industry.
Each metal has its own properties, which will allow it to solve problems that the other may not be able to solve effectively.
In applications where conductivity and miniaturization are important, copper can be especially valuable.
Aluminium can be beneficial where low weight, cost and corrosion resistance are significant.
The best material will then depend on the use.
When buying copper or aluminum, what should buyers consider?
It is important for industrial buyers to define their material needs prior to requesting quotations.
Important factors include:
Grade
Chemical and physical properties may vary between different grades.
Dimensions
Indicate the desired length, width, thickness, diameter, etc.
Quantity
The volume required may impact the price, availability, packaging and logistics.
Purity and Composition
Chemical composition can be important in applications that require control of material properties.
Certification
Depending on the application, buyers might need inspection reports, certificates of analysis, or other documentation.
Why Work With an Experienced Non-Ferrous Metal Supplier?
Purchasing industrial metals is not just about searching the web for a listed product.
Certain businesses may need certain grades, sizes, quantities, documentation, and delivery needs. A supplier who has worked with non-ferrous metals would be able to assist in coordinating these needs and finding an appropriate material.
Balaj Metaux is dealing with non-ferrous metals such as copper and aluminium products with industrial buyers. The company is involved in sourcing according to specifications, quantity, and destination, assisting businesses in sourcing materials for manufacturing, etc.
It is best to first establish the technical requirements of an application, for companies that are not sure if copper or aluminium is suitable for a specific application.
Final Thoughts
There is no single answer to the copper vs aluminum debate.
Copper has excellent electrical and thermal conductivities, and aluminium has significant weight reduction benefits and can be an economic option for many applications. Both metals have wide applications, are recyclable and are vital to today’s industry.
When selecting either, take into account all the application needs: conductivity, weight, size, durability, corrosion, manufacturing requirements, cost and availability.
The idea for industrial buyers is to not only identify the cheapest metal, but to identify the best deal. It should be used to choose the material that provides the desired performance at the desired overall cost.