General

Different Processes of Metal Extrusion

Extrusion can be defined as the process of pushing a heated billet or slug of metal through a preformed die to mold it into a carefully shaped cross-section profile. Pressure is applied using a hydraulic press.

This has many advantages, particularly for industrial fields. Extrusion is capable of producing highly complex cross-sections while simultaneously creating quality surface finishes. Materials that undergo this process are made to be durable; you won’t have to worry about tears and damage as the force applied won’t result in cracks. And, there’s a variety of metals and alloys, like those available from a copper extrusion supplier, for example, that can go through this procedure.

Metal extrusion has many processes. Here are two of them:

Hot Extrusion

This involves heating metal and forcing it through the die while it’s still in a molten state. Depending on the material used, the temperature can be as low as 650 and as high as 1,300 degrees Fahrenheit. If it isn’t hot enough for recrystallization, it may struggle to pass through the die.

The metal emerges from the gap as a long, continuous bar with the same cross-sectional shape as the die’s opening. Lubricants can reduce friction,so the surface of the mold is protected. Graphite is used for non-ferrous alloys, while glass is for hot steel. The process produces a wide array of configurations, including complex, asymmetrical, and non-uniform shapes.

What’s good about this process is it requires less force than cold extrusion. The end product is free from strain hardening, as well. But, it may result in a low surface finish due to scale formation on the extruded part. It’s also pretty high maintenance and could wear out the die. Copper, magnesium, steel, and aluminum are some of the most commonly used metals for this procedure.

Cold Extrusion

Also known as impact extrusion, the process involves forcing metal through a die while at room temperature. The material used usually comes in slugs, which will be poured into the die’s feeder. Pressure will then join them together to form a solid object.

Copper, lead, tin, aluminum alloys, and titanium are some materials perfect for cold extrusion. They’re used to create parts such as collapsible tubes, gear blanks, and cylinders. Manufacturers in the automobile section have also found a wide application of this process for engine control, fuel supply, and safety systems.

What’s great about cold extrusion is its high mechanical properties, quality surface finish, and lack of oxidization. But, it requires extreme force, and the end product is accomplished through strain hardening.

Both processes are capable of creating high-quality products fit for any field, whether it’s automobile or industrial. Get in touch with a copper extrusion manufacturer to learn more about these procedures or purchase cross-sectional metal materials.