Carbon Steel vs Aluminum | Progressive Products

Carbon steel and aluminum are two of the most common metals in manufacturing today. Still, they differ significantly in how they are made, their use, and their general properties. In this article, we’ll compare carbon steel and aluminum so that you can decide which material will work best for your pneumatic conveying system.

What is Carbon Steel?

Carbon steel is a versatile iron-carbon alloy made by heating iron and carbon together. Because it’s easy to work with and relatively inexpensive, carbon steel is used in many industries to make everything from auto parts and construction beams to electrical wiring and tools that require high strength properties and wear resistance.

Carbon steel can be graded with either a low, medium, or high-carbon steel content, with the amount of carbon in the steel determining its strength, flexibility, and hardness.

Low-carbon steel is characterized by low hardness while staying highly flexible and tough.
Medium-carbon steel also has a low hardness and lower flexibility but has increased strength and toughness.
High-carbon steel has the highest hardness and strength rating but is also inflexible and brittle.

In general, the more carbon in the metal, the stronger it will be, but too much carbon makes the steel fragile. Manganese, cobalt, silicon, and chromium are common elements added to carbon steel to create different carbon steel variants. Regardless of type, however, all carbon steels are vulnerable to corrosion.

What is Aluminum?

Aluminum is a silver metal made from bauxite ore. It is stronger and more malleable than copper and 2.5 times lighter than carbon steel. Additionally, aluminum has a higher melting point than carbon steel and can withstand intense heat without warping or melting. It is an excellent conductor of electricity, rating second only to copper. Abundant and low-cost, this malleable metal is also one of the lightest on the planet, with the highest strength-to-weight ratio of any metal.

Unlike carbon steel, aluminum has excellent corrosion resistance properties. This resistance doesn’t mean it's impervious to rust, however. Aluminum can corrode when exposed to direct water or chlorine bleach. However, it can be minimized by applying a protective coating to the aluminum to protect it from direct exposure.

Which is Better?

The decision on whether you should go with a pneumatic conveying part made from carbon steel or aluminum depends on what the part will be used for, what type of system it will be used in, and what elements the system will be exposed to.

Take pneumatic conveying elbows, for example: because aluminum elbows are made from a softer material, they wear out quickly when exposed to abrasive materials such as plastic pellets. In this case, you’re better off using carbon steel elbows as they are durable and abrasion resistant. If, however, the materials you’re transporting are non-abrasive plastics or if you’re using air-only conveying lines, aluminum elbows will be a cheaper alternative.

Carbon steel parts are generally durable, economical, readily available, and reasonably priced. Their corrosion vulnerability can be mitigated by painting parts out in the elements or areas where rust is a concern.

Aluminum parts are naturally corrosion resistant, and because they are 2.5 times lighter than carbon steel, they are easier to use and quicker to fasten. They are more expensive than carbon steel parts, and their tendency to wear down quickly in the wrong environment may become costly in the long run.

As you can see, both carbon steel and aluminum are excellent materials for pneumatic conveying systems. Which one you use will depend on which unique properties make them suitable for your project. If you need a bare elbow, a Ceram-Back®, or any one of our other abrasion-resistant options, contact us to get a quote. At Progressive Products, if you can imagine it, we can make it happen.

What are the main differences between carbon steel and aluminum?

Carbon steel is an iron-carbon alloy known for high strength, hardness, and wear resistance, but it is vulnerable to corrosion. Aluminum is a lighter, naturally corrosion-resistant metal with a higher melting point and excellent strength-to-weight ratio — approximately 2.5 times lighter than carbon steel. Carbon steel comes in low, medium, and high-carbon grades with varying strength and flexibility; aluminum is more malleable and better suited for environments where weight and corrosion are concerns.

Which material is stronger: carbon steel or aluminum?

Carbon steel is generally stronger in terms of tensile and yield strength, particularly high-carbon grades. However, aluminum has a superior strength-to-weight ratio — it delivers comparable structural performance at a fraction of the weight. In pneumatic conveying applications, carbon steel is preferred where durability and abrasion resistance are critical, while aluminum is a practical choice for lighter-duty applications or where weight reduction is a priority.

How does the weight of aluminum compare to carbon steel?

Aluminum is approximately 2.5 times lighter than carbon steel. This makes aluminum components easier to handle, quicker to fasten, and better suited for applications where minimizing weight is important. In pneumatic conveying, lighter components can simplify installation and maintenance, but this advantage must be weighed against aluminum's susceptibility to faster wear in abrasive environments.

Which material offers better corrosion resistance in industrial environments?

Aluminum offers significantly better corrosion resistance than carbon steel. It naturally forms a protective oxide layer that guards against rust in most industrial environments. Carbon steel is vulnerable to corrosion when exposed to moisture or chemicals and typically requires painting or coating to protect components used outdoors or in wet conditions. Aluminum can corrode when exposed to direct water or chlorine bleach, but this can be minimized with a protective coating.

When should aluminum be used instead of carbon steel in manufacturing?

Aluminum is the better choice when conveying non-abrasive materials, when weight reduction is important, or when natural corrosion resistance is needed without additional coating. For example, aluminum elbows work well for air-only conveying lines or with non-abrasive plastics. In abrasive applications — such as conveying plastic pellets — aluminum wears out quickly and carbon steel elbows are the more durable, cost-effective option.

What industries commonly use carbon steel vs aluminum components?

Carbon steel is widely used in heavy industry, mining, construction, and abrasive material handling where strength and durability are paramount. Aluminum is common in food processing, pharmaceutical manufacturing, and plastics conveying where corrosion resistance and weight matter. In pneumatic conveying specifically, the choice between the two depends on the material being conveyed, the system's operating environment, and the expected level of abrasion.

How do cost, durability, and maintenance compare between carbon steel and aluminum?

Carbon steel is generally the most economical choice for applications requiring durability and abrasion resistance. It is readily available, performs exceptionally well in high-wear environments, and its susceptibility to corrosion can be effectively managed with paint or protective coatings when necessary. Aluminum, while costing more per pound than carbon steel, is significantly lighter. Because aluminum weighs much less, less material is required to manufacture an elbow, often making the finished part less expensive despite the higher cost per pound. Aluminum also offers excellent natural corrosion resistance, eliminating the need for coatings in many environments. However, aluminum is not as wear-resistant as carbon steel and will typically wear more quickly in abrasive applications. Selecting the right material ultimately depends on balancing cost, weight, corrosion resistance, and expected service life for the specific application.