Advantages of an Aluminum Electric Motor

Despite the great copper vs aluminum debate, there are motor manufacturers who use aluminum wire in their smaller motors. This is a huge benefit to the manufacturer as it reduces the cost of production.

The challenge is properly connecting the ends of the aluminum wire to ensure conductivity. To do so, they use high-pressure piercing crimp connectors.

Low Cost

Compared to steel, aluminium is far cheaper. It also has superior thermal and electrical conductivity. This means that it can dissipate heat faster and more efficiently. As a result, it reduces motor losses and increases performance. Moreover, it has a lower density and is easier to die-cast.

For these reasons, it is no wonder that more and more companies are switching to aluminum electric motors. The trend is even more apparent in the auto industry, where aluminium has become an important material. Nemak, for example, has won contracts to produce aluminium battery housing components worth up to $830 million.

A totally enclosed non-ventilated aluminum motor body is suitable for scenarios containing dirt and damp. It is also safe for environments containing Group B gasses (hydrogen, butadiene, propylene oxide and ethylene oxide) and coal dust. However, it does not form an airtight frame and needs cooling fans. This type of motor should be placed in a UL-approved explosion-proof enclosure.

Corrosion Resistant

Despite the fact that aluminium is a reactive metal, it has good corrosion resistant properties due to the formation of a protective oxide film on its surface. This layer is hard and adherent to the metal, so any accidental abrasions are automatically repaired.

This coating can be applied through powder coating, an electrostatic process in which a negatively charged aluminium powder is deposited on the surface of the aluminum motor body. The coating is then cured with heat. The process is environmentally friendly and produces a hard, durable coating that is water and corrosion resistant.

The aluminium-copper alloys used in electric motors have very good corrosion resistance. However, they cannot be used in explosive atmospheres. These alloys contain copper, which is flammable and therefore not acceptable in explosion-proof enclosures. Additionally, these alloys can cause sparks if they are rubbed with other metals. This is not an issue in normal use, but it can be a problem when attempting to solder the windings.

High Strength

Using aluminum in a motor’s design can provide a significant cost savings. The light weight of aluminum means that fewer fixing bolts are required, saving materials and assembly time. Its ductility also allows engineers to make more use of space inside the motor, increasing efficiency and power output.

A motor’s magnet wire construction is also an opportunity for performance gains. While copper is the standard magnetic wire material, aluminium is a commercially available alternative. However, due to the lower conductivity of aluminium, larger wire diameters would be required to achieve the same power outputs.

Fortunately, new manufacturing techniques such as Advanced Liquid Pressure Forming can selectively reinforce areas of a component with one of these performance materials, reducing the diameter of the wire and improving its conductivity. This approach may be especially useful in an electric vehicle where the high cost of battery manufacture motivates the pursuit of lightweighting strategies. These approaches can help to balance the inverse relationship between mechanical strength and electrical conductivity that has long plagued magnet wire materials.

Lightweight

Aluminum is a lightweight material, making it easier for electric motors to be installed within a vehicle. This allows for a lower center of gravity, and therefore greater fuel efficiency.

Additionally, aluminum can withstand harsh environmental conditions. This makes it a good choice for use in motors that are exposed to dirt and dampness. Wellste offers many types of aluminium motor enclosures, including explosion-proof aluminum motor bodies.

As the demand for electric vehicles grows, companies that produce aluminum parts are experiencing strong growth in their businesses. This includes Mexico's Nemak, Canada's Linamar and France-based Constellium. For example, Linamar is investing in producing the battery tray for EVs, which could account for 20% of its sales volume by 2023. This is because many of the same processes that are used for traditional ICE-powered cars can be reused to make EV components. This will reduce both the time and cost of manufacturing EVs.