Aluminum and the Auto Industry

Aluminum has been used to manufacture automobiles for well over a hundred years. The first sports car featuring an aluminum body was premiered at the Berlin International Motor Show in 1899. In 1901, Carl Benz, who went on to co-found Mercedes Benz, constructed the first aluminum car engine. Due to initial difficulties in metalworking with aluminum and its high price at the time, it took over 60 years for aluminum to become widely used in the auto industry. In 1961, Land Rover’s mass-produced Buick 215 featured an eight-cylinder V8 engine made from aluminum. The lightness of the engine was a revelation, and it became an instant hit with race-car drivers. In 1997, Audi started production of aluminum body cars. The use of aluminum reduced the weight of the car bodies by up to 239 kg and paid great dividends in reducing fuel consumption.

Today, aluminum is the second most used material in the auto industry, next to steel. It’s believed that 1 kg of aluminum can replace up to 2 kg of steel or cast iron in manufacturing.

What is Aluminum?

Aluminum is a metallic element. It’s classified with tin and lead in the “poor metal” category, as it’s extremely malleable. It’s been used by human civilization since ancient times. Aluminum oxides have been discovered in pottery artifacts from Ancient Egypt and Rome. At first, scientists believed aluminum to be rare and extraction was difficult. We now know that it’s the third most common element in the Earth’s crust and the most common metallic element on Earth. Aluminum blends easily to make lightweight but strong alloys. Aluminum is very light, conducts heat and electricity very well, and is non-magnetic. These properties make it ideal for many uses, from construction to cooking utensils to auto manufacturing.

How is Aluminum Different from Other Metals?

Aluminum has a unique combination of properties that make it indispensable in the automotive industry:

Weight

Aluminum is light, with a density of one-third that of steel. Despite its lightweight nature, aluminum maintains impressive strength, ensuring structural integrity and performance in automotive vehicles.

Strength

Aluminum is strong. Aluminum alloys have tensile strengths ranging from 70 to 700 MPa. Unlike steel, aluminum does not become brittle at low temperatures. Rather, its strength increases when cold. This makes aluminum an excellent choice for vehicles in locations with large variations in temperature and environmental conditions.

Flexibility

Aluminum’s strength is combined with flexibility, meaning it can flex under load and bounce back from the force of impact. This makes aluminum an ideal material for applications where resilience and durability are essential, such as in automotive crash structures and aircraft components. Its ability to withstand deformation without permanent damage ensures enhanced safety and structural integrity in critical environments.

Malleability

Aluminum is extremely malleable and can be extruded into any desired shape by passing it through a die. Aluminum can be extruded, either hot or cold. It can be further manipulated through bending and forming operations.

Conductivity

Aluminum is an excellent conductor of heat and electricity. An aluminum conductor weighs around half the equivalent copper conductor with the same conductivity. Aluminum’s high thermal conductivity facilitates efficient heat dissipation, enhancing the performance and longevity of engine components and electrical systems. Its electrical conductivity ensures reliable power distribution and transmission within vehicles.

Reflectivity

Aluminum is a good reflector of both light and heat. This makes aluminum a good choice for automotive lighting systems and heat shields, which protect the exhaust system, fuel lines, and electrical wiring from the radiant heat generated by the engine and exhaust system and contribute to the vehicle’s overall safety.

Corrosion Resistance

Aluminum reacts with the oxygen in the air to form a microscopically thin layer of oxide. This layer is only 4 nanometres thick but provides excellent protection against corrosion. It even repairs itself if damaged. Aluminum body panels and components can withstand exposure to harsh environmental conditions, such as moisture and road salt, without succumbing to corrosion.

Are Cars Made of Aluminum?

Aluminum is commonly used in the automotive industry. Its lightweight nature makes it an attractive material for various automotive components, including body panels, engine blocks, wheels, and suspension parts. The use of aluminum in the automotive industry helps to reduce overall vehicle weight, which can improve fuel efficiency and performance while also enhancing handling and agility. Additionally, aluminum’s corrosion resistance contributes to the durability and longevity of automotive components, making it a preferred material choice for many manufacturers.

Why Does the Auto Industry Need Aluminum? How is it Used?

The auto industry uses aluminum for the vehicle frame and body, electrical wiring, wheels, lamps, paint, transmission, air conditioner condenser and pipes, engine parts (pistons, radiator, cylinder head) and magnets (for speedometers, tachometers, and airbags).

Using aluminum for automobile manufacture instead of steel gives several benefits:

Performance Benefits

On average, aluminum is 10% to 40% lighter than steel, depending on the product. Vehicles made from aluminum have better acceleration, better braking, and better handling. Aluminum’s rigidity gives drivers more immediate and precise control, while its malleability allows designers to engineer vehicle shapes optimized for maximum performance.

Safety Benefits

Aluminum can absorb twice as much energy in a crash as the equivalent weight of steel. Aluminum can be used to increase the size and energy absorption capacity of a vehicle’s front and back crumple zones, enhancing safety without increasing weight. Vehicles made from lighter aluminum require shorter stopping distances, helping to prevent collisions.

Environmental Benefits

Nearly 90 percent of automotive aluminum scrap is recovered and recycled. Recycling 1 ton of aluminum saves energy equivalent to 21 barrels of oil. Using aluminum auto manufacturing gives a 20 percent smaller lifecycle CO2 footprint than steel. The Aluminum Association’s report “The Element of Sustainability” found that replacing a fleet of steel vehicles with aluminum vehicles can save 108 million barrels of crude oil and avoid 44 million tons of CO2 emissions.

Fuel Efficiency

Vehicles with aluminum components can be 24 percent lighter than those with steel components. This saves 0.7 gallons of fuel per 100 miles, a saving of 15 percent in fuel consumption over steel vehicles. Similar fuel savings are made when aluminum is used in hybrids, diesel, and electric vehicles.

Durability

Vehicles with aluminum components benefit from less need for rust repair, and they enjoy an increased lifespan. Aluminum components are ideal for vehicles in challenging environments, including off-road and military.

Why is Aluminum Used in Cars?

Aluminum is used in cars due to its lightweight properties, corrosion resistance, and strength-to-weight ratio. These qualities make it an ideal material for various automotive components, including body panels, engine blocks, wheels, and suspension parts. By incorporating aluminum into car manufacturing, automakers can significantly reduce vehicle weight, improving fuel efficiency, enhancing performance, and increasing overall agility and handling. Aluminum’s resistance to corrosion ensures the durability and longevity of automotive parts, contributing to the reliability and lifespan of vehicles. Using aluminum in cars has played a big part in developing lighter, more efficient, and durable vehicles.

What Other Metals Are Typically Used in the Construction/Repair of Vehicles?

Steel is still a mainstay of auto manufacturing. It’s used in the body and frame, the fuel tank, the engine block, axles, gears, brakes, and cables. Copper is used in electrical wiring. Brass is used in bushings and the radiator. Other metals used in lesser amounts include chromium, lead, magnesium, manganese, nickel, and zinc.