An alloy is a metal formed by a metal with a metallic or non-metallic element. They were combined primarily to resist corrosion and become stronger, softer, and ductile than their pure components. Examples of alloys are brass, which is made of copper and zinc, while steel, which is made of iron and about 2% carbon.
So, what are alloy wheels? Alloy wheels are wheels made of aluminum or magnesium. Compared to steel wheels, they are lighter, more stylish, and reliable in heat dissipation and vehicle performance. However, alloy wheels are less durable and expensive to replace.
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All You Need to Know About Alloy Wheels
Alloy wheels are also known as “mag wheels” because in the early days of wheel manufacturing until the 1960s, magnesium was a preferable choice for vehicles meant for racing due to its low density of 1.8.
Magnesium is a weight-saving metal for racers and engineers. Light vehicles promise a speedy ride quality. However, magnesium had setbacks like cracking and corrosion.
Magnesium wheels took a backseat in the 1960s -1970s because alloy wheels made of aluminum were introduced. They are also called alloy rims. This metal became widely used in motorsports because it is more durable than magnesium.
Nowadays, despite what alloy wheels look like, the term “mag wheels” was used to cover most modern materials that were created out of die-casting.
Are Alloy Wheels Aluminum?
Aluminum wheels are sometimes called “alloy wheels,” but they are made of nickel and aluminum. Most aluminum wheels today are produced from molded molten aluminum. Hence, they are known as cast aluminum alloy. On the other hand, forged aluminum alloys are stronger but lighter than alloy wheels.
Types of Alloy Wheels
Alloy wheels differ in features and cost because of the following fabrication methods.
This method follows one or multi-step processes of heating and beating numerous magnesium alloys. As a result, it has higher toughness and ductility than aluminum wheels.
2. Low pressure die casting
Die casting uses a crucible (ceramic or mold that can stand high heat). It is filled with molten magnesium but sealed with pressurized air or a cover gas mix.
When a steel die was placed on top of the crucible, the pressurized air or cover gas mix forces the molten magnesium to rise to the filler tube until it reaches the die.
The alloy produced in this method has better ductility than magnesium or aluminum alloys.
3. High pressure die-casting
In this method, the molten magnesium is poured on a filler tube called a shot sleeve. Then, high pressure is applied to trigger the piston to push the metal into the die, which was placed on top of a large machine. When the magnesium is solidified, the die is opened, and a new magnesium wheel is produced.
High-pressure die-cast wheels are less ductile and have lower strength. Still, they are more corrosion-resistant and cheaper to produce.
4. Gravity Casting
This method refers to pouring molten metal from the crucible into a mold without using pressurized gases, vacuums, or centrifugal force. As for aluminum, it can be injected into the mold. Then, machining gives the alloy product the desired finish.
This method started in the 1920s and has been preferred because the tooling costs are the most affordable. In addition, it provides desired ductility, flexibility in design, and short development time that are sufficient for small batch production.
This method is used to create one-piece, two-piece, and three-piece forged wheels.
Overall, cast wheels are heavier because the mold was prepared to retain strength, while forged wheels are stronger, lighter, and more expensive than cast wheels because of their elaborate fabrication process.
Advantages of Using Alloy Wheels
1. Reliable Vehicle performance
Alloy wheels are easier to control than steel wheels because they are lighter. In addition, since it reduces the overall weight of the vehicle, one can maneuver the car in a more stable manner.
Less weight means:
- Less strain on vehicle suspension, which results in better acceleration, steering, and braking
- Less fuel consumption
- Longer tire life and less car maintenance
- Comfortable ride
In other words, the reduced weight of alloy wheels car compared to its traditional counterparts make it faster and more convenient to stop and start the vehicle with less energy. It also consumes less fuel to change speed or brake on the road.
2. Better Heat Conduction and Dissipation
Driving with hot tires is unsafe, so having alloy wheel mean you are assured that it can conduct and effectively dissipate heat on critical vehicle parts like brakes. This feature keeps the car safe because it prevents overheating and overusing brakes.
3. Aesthetic Style
Alloy wheels are more stylish because they are more ductile. So, expect more choices when it comes to spoke designs and sizes ranging from 14-inch wheels to 28 inches.
Automakers allow custom alloys wheels so you can add another level of control to your vehicle.
On the other hand, the usual rim size of steel wheels is 16-inch. They cannot be installed on vehicles designed for alloy wheels.
Die-cast alloy wheels can accommodate different aesthetic finishes due to mold preparation. However, unlike steel wheels which were produced through welding, it cannot produce a variety of attractive spokes.
Therefore, if you want to make your vehicle stand out from the rest, alloy wheels can offer the visual appeal you want.
Disadvantages of Using Alloy Wheels
1. Less Durable
Alloy wheels are not as sturdy as steel wheels when used on rough terrains. They are more subjected to dents and cracks after prolonged use. You can even find curb rashes on the wheels, especially when you drive them in poor or demanding road conditions.
On the other hand, steel is malleable so repairing steel wheels by hammering the dents is possible.
Since alloy wheels cannot be repaired, buying new alloy wheels can be pricey. For example, aluminum alloy rims range from $110-130.
Die-cast aluminum alloys are expensive to fabricate because they need to be mixed with other metals such as copper, magnesium, and nickel.
It reduces the cost of plating when aluminum is mixed with 8 % copper. When it is mixed with magnesium, it improves its tensile strength from 21,000 PSI (pounds per square inch) to 32,000 psi. Adding zinc to aluminum can increase rigidity and a higher surface finish.
On the contrary, steel wheels are easy to produce because their manufacturing cost is around 70%-80% less than alloy wheels. Depending on the size of the steel rim, the cheapest one can buy is $30.
It is confusing at first to identify what are alloy wheels made of. It’s a good thing to recount its little background and compare its features, pros, and cons with steel wheels.
Interestingly, alloy wheels proved more beneficial because of their lightweight and aesthetic advantages. If you are critical of vehicle performance and fuel consumption, alloy wheels promise better handling. Unfortunately, its main disadvantages are durability and high maintenance cost.
If you have other questions about steel wheels, feel free to share your thoughts.