No matter what industry your business is in, your products are only as good as the forged parts you order. High-quality products require strong, well-manufactured parts. Often, companies offer either steel or aluminum for metal components.
If you’re on the fence about which material to use for a part project, a forging company can help you make that decision. High-quality forgers offer various options for part materials, such as the forged aluminum solutions from Anchor Harvey. While steel may be cheaper per pound, the lighter aluminum material may be best for your parts.
Strength and Weight
While it’s commonly believed that steel is more robust than aluminum, there are many caveats to this argument. Like any lower-density material, aluminum is lighter than steel, but its weight-to-strength ratio often isn’t far off from steel’s weight-to-strength ratio.
Even if you chose steel that is much stronger than aluminum, that strength might prove problematic in the long-run. Carbon steel, one of the most common types used for forging, has a higher risk of corrosion than aluminum. Furthermore, if your part will be used in a cold environment, aluminum may be a better choice, since aluminum increases in strength when cold.
If weight is a significant concern, aluminum is a better choice than steel as it weighs far less. On average, steel weighs 2.5 times more than aluminum, since it contains more carbon. That can be problematic if you need to limit the weight of individual forged parts since heavier elements can slow down a vehicle or cost more to transport.
Although you can find light steels for cheaper than aluminum, that density decrease comes with a reduction in strength. Most lightweight metals are weaker and more prone to breaks than aluminum. When forging, that means your part is more likely to break during the process and need to be redone. After forging, it means your part may be more susceptible to breakage than a similar aluminum part.
Aluminum is far less likely to rust than steel because it’s naturally coated with an oxide film that prevents it from corroding, rusting, or scratching. If you use steel, you’ll need to add corrosive-resistant coatings to the final product, which often still doesn’t protect your part from corrosion as well as aluminum’s oxide film.
When corrosion is a significant concern for your part, aluminum is your best bet. Besides its natural coating, you can add additional powder or brushed coatings that further protect your part. As such, it’s much easier to prevent an aluminum part than a steel one from corroding. This makes aluminum ideal for outdoor applications.
Steel is a poor conductor of electrical or thermal energy. That is why aluminum is often used in cables, motor, appliances, and television dishes. Parts used in a larger system needing conductive elements will most likely need to be made with aluminum, not steel.
While copper is more conductive than aluminum, it’s less corrosive and lighter. These characteristics often make aluminum the best choice when conductivity is a factor.
Aluminum is much easier to manipulate and bend than steel, making the forging process easier and faster. If you need to forge your part into particular shapes or make the part thinner, aluminum will cooperate more than steel. Since it’s ductile, aluminum can be stretched thinner and more precisely as well.
Trying to manipulate steel as precisely as aluminum can result in the material breaking or cracking. Since it’s heavier and stronger, it resists more than aluminum during forging. Thin parts with coiled shapes should be forged with aluminum.
Steel generally costs less per pound than aluminum. However, market costs can fluctuate for both parts, making the price difference between the materials vary greatly. Additionally, even though it costs more per pound, how light aluminum is may offset some of that upcharge.
The upfront cost of aluminum may be more than steel. Nonetheless, its non-corrosive coating, lighter weight, and malleability may make it equal or lower in price than steel. Before letting costs deter you from choosing aluminum, consider if its properties may make your part less likely to break or corrode with time than steel.
Steel vs. Aluminum Parts
Many companies struggle to choose between steel or aluminum. For many projects, though, aluminum is often the better choice. It can be more easily manipulated, weighs far less, and is resistant to corrosion. Consider the long-term use of your part before opting for steel on your next project.