Aluminum Extrusions: Everything You Need to Know Before Buying

Ever wondered how the sleek frames of modern automotive or aerospace structures come to life? The answer is aluminum extrusion: a process that molds aluminum alloy into defined shapes to be used in endless industrial applications. Aluminum’s high corrosion resistance and strength-to-weight ratio make its extrusion process a cornerstone in manufacturing.

The applications of aluminum extrusions are vast and varied, stretching across automotive, aerospace, electronics, and beyond. From creating sturdy frames and enclosures to designing efficient heat sinks and workstations, aluminum extrusions fulfill structural needs and drive innovation in product design. The customizability of aluminum profiles, achieved through machining and anodizing processes, further amplifies its utility and appeal across many industry sectors.

In this guide to aluminum extrusions, we’ll go through all the basics and technical aspects as well as its almost limitless industrial applications. You’ll learn why extruded profiles are important tools for today’s product designers and manufacturers. By the end, you’ll know whether you should make aluminum extrusions a part of your next project.

Read on to learn all about aluminum extrusions and find out if it’s the solution to your manufacturing needs.

The Extrusion Process

To get started, here’s a look at what the aluminum extrusion process entails:

• Die design and preparation: The die, a specialized tool crafted from hardened tool steel, is the blueprint of the desired profile. It’s designed and prepared to precisely shape the aluminum as it passes through.
• Billet heating and loading: The aluminum billet is a solid cylinder that gets heated to a malleable state, then it’s ready to be loaded onto the extrusion press where it will be shaped.
• Extrusion: Next, the heated billet gets pushed through the die under high pressure, forcing it to fit the designed profile. 
• Cooling and cutting: Post-extrusion, the newly formed profile is cooled to solidify its shape, then cut into specific lengths.
• Finishing and inspection: The extruded profiles undergo various finishing processes, like anodizing for enhanced corrosion resistance or machining for added functionality. A thorough inspection ensures each profile meets the stipulated quality standards to become high-quality aluminum products.

Types of Aluminum Extrusion

The diversity in aluminum extrusion types is a testament to aluminum’s adaptability. Each type serves distinct purposes, catering to a myriad of industrial applications. Let’s look at how each type works and what they’re often used for.

Direct extrusion

Also known as “forward extrusion,” direct extrusion is the most common type wherein the billet is pushed through the die by a hydraulic press. Its straightforwardness makes it a popular choice for creating solid and hollow tubes for automotive frames or construction purposes.

Indirect extrusion

In the indirect extrusion process, the extrusion die remains stationary while the billet and container are the only parts that move. This reduces friction, allowing for more complex and precise profiles. It’s ideal for aerospace applications where tighter tolerances are required.

Impact extrusion

Impact extrusion sets itself apart with a high-velocity punch that forces the billet through the die. This method does a great job of creating hollow objects like cans, round tubes, and other container shapes, which is why it’s often used in the product and food packaging sector.

Hydrostatic extrusion

With hydrostatic extrusion, the billet is submerged in fluid within a pressurized container in order to extrude it through the die. This method allows for higher extrusion speeds and tighter tolerances, making it suitable for high-precision automotive and aerospace components.

Why Use Aluminum Extrusion?

Like the Swiss Army knife of manufacturing, aluminum extrusion caters to many different industrial needs. Let’s explore the advantages of aluminum extrusion and how they make it ideal for certain applications.

• Lightweight strength: This makes it a sought-after material in automotive manufacturing. For instance, aluminum framing in gas and electric vehicles alike reduces their weight, enhancing fuel efficiency without compromising structural integrity.
• Design versatility: You can create intricate, custom aluminum extrusion profiles for aerospace prototyping and manufacturing. These extruded aluminum profiles can be precisely engineered to adhere to even the strictest standards. 
• Sustainability: The fact that you can recycle aluminum makes it an environmentally and economically sustainable choice. In construction projects, aluminum enclosures can be made en masse and recycled after use, supporting sustainable building practices and saving money.
• Wide range of applications: Aluminum extrusion’s applications are boundless. From heat sinks used to dissipate heat in electronics for optimal functionality, to sturdy, lightweight, bicycle frames and furniture casters, it’s the perfect choice for a vast array of industrial and commercial needs.

Challenges Involved With Aluminum Extrusion

While aluminum extrusion clearly offers many advantages, it does come with a few challenges as well. Next, we’ll address the most common issues and offer the best solutions. 

Material waste

A notable challenge in aluminum extrusion is material wastage, especially during the die preparation and cutting phases. Any discrepancy in die design or the extrusion process can lead to overproduction of scrap material.

Using precise computer-aided design (CAD) software and advanced cutting technologies for die can help. Plus, recycling the scrap aluminum can offset the cost and environmental impact of any wasted material.

High energy consumption

Aluminum extrusion is energy-intensive, especially during the billet heating phase. This can escalate operational costs and carbon emissions. However, energy-efficient heating systems and recovering heat from the extrusion process can cut down your energy use. Using renewable energy sources can also reduce your environmental impact.

Surface quality issues

Getting a nice, smooth surface finish can be hard when extruding more complex, intricate profiles. Scratches or die lines can affect the aesthetic and functional quality of the extruded profiles.

One solution to this is using well-designed and well-maintained dies. Surface treatment techniques, like anodizing or powder coating, can also enhance the surface quality of your extruded profiles.

Types of Aluminum Used in Extrusion

Understanding the properties of different alloys can help you choose the right one for your project requirements. Commonly used alloys include 6061 and 6063, known for their good strength-to-weight ratio and corrosion resistance. 

Aluminum 6061 is often used to fabricate automotive frames because of its strength, weldability, and high corrosion resistance. On the other hand, 6063 has a finer surface finish and even higher resistance to corrosion, making it a great choice for window frames.

7075 Aluminum is another choice with a much higher strength-to-weight ratio than that of 6061, making it an ideal candidate for aerospace and military applications. But like 6061, it can be heat treated to further enhance its mechanical properties, offering a spectrum of uses across different sectors.

A fourth popular option, 8020 aluminum — also referred to as T-slot aluminum extrusion — is a good choice for modular framing and structural applications. The term “8020” refers to the brand, 80/20 Inc., a leading manufacturer in this field. Comparable to 6061 in terms of strength and corrosion resistance, 8020 aluminum features a T-slot design for easy assembly, accommodating connectors, fasteners, and other accessories without the need for welding. 

Shapes That Can Be Extruded

The aluminum extrusion process is incredibly versatile. Here are some common shapes that can be extruded:

Solid Shapes

Solid extrusions are a staple in many industries due to their strength and simplicity. They can take on a variety of cross-sectional profiles, such as squares, rectangles, circles, or any other custom-designed shape.

Hollow Shapes

Hollow extrusions are lighter in weight yet maintain a high level of structural integrity. Common hollow shapes include tubes, pipes, and custom profiles with voids. 

Semi-Hollow Shapes

Semi-hollow extrusions offer a middle ground between solid and hollow shapes, providing a balance of strength, weight, and cost. They are used in applications that require structural robustness while still benefiting from weight reduction.

Multi-Void Hollow Shapes

Multi-void hollow shapes have complex cross-sections with multiple voids. They are ideal for applications requiring intricate, lightweight, and strong profiles.

Custom and Complex Shapes

The flexibility of the extrusion process allows for the creation of highly complex and custom shapes to meet specific design requirements. These could include a combination of solid, hollow, and semi-hollow sections within a single profile, catering to the sophisticated needs of modern industries.

Heat Sinks

Extruded aluminum heat sinks are crucial for thermal management in electronics and electrical devices. The extrusion process can create fins and other complex features to maximize heat dissipation.

Channels and Angles

Channels and angles are basic yet essential shapes extruded for a variety of structural, architectural, and industrial applications. They provide support, framing, and alignment.

T-slots

The T-slot design allows for easy attachment of connectors and accessories. They enable fast and flexible assembly, facilitating the construction of framing systems, workstations, and other structural applications. 

What’s Next? The Future of Aluminum Extrusion

As industries evolve, so does aluminum extrusion. The drive towards lightweight, durable, and sustainable solutions propels the growth in popularity of aluminum extrusion.

Emerging technologies like the advancement in CNC machining and anodizing processes continue to refine the extrusion process, expanding its possibilities. However, challenges like the material waste and energy consumption involved in extrusion processes call for innovative solutions.

The rise of electric vehicles and the increasing demand in aerospace and construction sectors also spell growth opportunities for aluminum extrusion. The development of new alloys with higher strength and better corrosion resistance promises to push the boundaries of what aluminum extrusion can achieve.

With these innovations and expanding applications on the horizon, the future of aluminum extrusion beams with potential and is ready to meet the burgeoning demands of modern industries.

From Billet to Brilliance: The Aluminum Extrusion Journey

Thanks to its lightweight yet high-strength character, cost-effectiveness, and boundless application across industries, aluminum extrusion holds a key role in modern manufacturing. It enhances functionality, innovates design, and fuels sustainability in each sector it touches. The horizon of aluminum extrusion stretches even further to propel these industries forward.

If this guide has sparked inspiration for your next manufacturing project, learn more about Zetwerk’s high-quality aluminum extrusions using custom dies. 

The path to turning your vision into tangible, high-quality products is within your reach. Take the first stride, and get a manufacturing quote from Zetwerk today!