How Are Aluminum Profiles Extruded?

Release time:2022-07-22

Aluminum extrusion has seen substantial growth in application in product design and manufacturing over the past few decades. According to Technavio, the demand for aluminum extrusion will increase by around 4 % globally between 2019-2023.

Perhaps you've heard of the manufacturing process and are interested in learning more about it and how it operates. This article will cover the entire subject of aluminum extrusion in detail.

What is the extrusion of aluminum?

Aluminum alloy material is forced into a die with a specific cross-sectional shape using the extrusion method. The metal is pushed through the die and out of the die aperture by a powerful ram. It appears just as it did in the die and is carried away along with a runout table.

Fundamentally speaking, the procedure is a really simple technique. 

Once you squeeze a tube of toothpaste with your hands, the same force is used. When you squeeze the toothpaste tube, it emerges as an aperture. The toothpaste tube's aperture serves a similar function to an extrusion die.

Extrusion Process

The actual extrusion method is very similar to the vintage Play-Doh Shape Maker. The Play-Doh flows out of the press in the shape of the chosen mold as you squeeze it through. The extruded aluminum adopts the aperture of the die's shape similarly.

You can extrude aluminum into any shape using strong hydraulic presses that can provide up to 15,000 tons of pressure. There are two primary techniques for extruding aluminum:

· Direct

· Indirect

Direct Extrusion

This method produces less friction than the direct method, which results in better heat regulation. Indirect extrusions typically produce higher-quality products that are more consistent. It might be a result of the applied force being largely constant. Additionally, the stability of the temperature guarantees improved grain structure and mechanical qualities.

Indirect Extrusion

The indirect procedure also referred to as backward extrusion, is distinct from the direct method. Here, the container and billet move concurrently while the die stays motionless. Manufacturers conduct this technique using a "stem." The stem that holds the ram in position must be larger than the size of the container. As a result, the stationary die is pushed through with the aluminum billet.

This method produces less friction than the direct method, which results in better heat regulation. Indirect extrusions typically produce higher-quality products that are more consistent. It might be a result of the applied force being largely constant. Additionally, the stability of the temperature guarantees improved grain structure and mechanical qualities.

The Steps of the Aluminum Extrusion Process 

Ten steps make up the extrusion procedure. We'll look at what they are now.

Prepare and transfer the extrusion die to the extrusion press

First, the H13 steel dies with a circular shape are manufactured. Or, if one is on hand, it gets taken out of a warehouse-like this one. The die must be warmed to between 450 and 500 degrees Celsius before extrusion to increase its life and ensure even metal flow. You can load the die into the extrusion press after heating up.

Warm up the aluminum billet.

The next process is to slice the billet, a long, coiled piece of aluminum alloy raw, from the material log. Then, preheat the oven to between 400 and 500℃. You can complete the operation with the billet's malleability increased by this method. Additionally, it makes sure it isn't molten.

Transferring the billet to the extrusion press 

Place the billet mechanically into the press after preheating it. But before you pour that into the press, ensure to add a lubricant. Sprinkle the releasing agent to the extrusion ram as well. The billet and ram won't stick together due to this procedure.

Fill the extrusion press container with billet material

The malleable billet is now in the extrusion press at this time. Here, the hydraulic ram has a pressure capacity of around 15,000 tons. The malleable billet is forced into the box by the pressure. Then, the aluminum components grow to fill the box's walls.

Press the material that was extruded up against the die.

Now that the box's wall is filled with aluminum material, it's forced up against the extrusion die. At this moment, the material is continuously under pressure. The only way it can move is via the die openings. It comes out of the die's apertures with a precisely formed shape.

Quench the extrusions 

Once the extrusion has emerged, a puller keeps it in position. When it comes out of the press, the puller shields it. You use a water bath or fan to uniformly cool the profile as the alloy travels along with the table. This procedure is "quenching."

Table-lengthen the extrusions

Use a hot saw to shear the extrusion as soon as it reaches the full length of the table. Throughout the entire extrusion procedure, the temperature is crucial. Even though the extrusion was quenched after exiting the press, it has not yet reached full cooling.

Reduce extrusions to room temp

The extrusions are moved from the runout table to a cooling plain when the shearing operation is complete. The profiles are kept there until they reach room temperature.

Stretching begins when they reach room temperature.

Transfer extrusions to the stretcher and align them

You'll probably notice some bends in the shapes, which you need to fix. You require a stretcher to repair this. Pull every profile mechanically until it is straight by holding it at both ends. They are specified through this process.

Extrusions are moved to the finish saw and are then cut to length.

You can now move the extrusions to a saw table as they are straight and work-hardened. You can now cut them into particular lengths, often between 8 and 21 feet. You can put them in an oven to age to the proper temper when the sawing operation is complete (T5 or T6).

Execute supporting actions (heat treatment, fabrication, and surface finishing)

You can heat profiles after finishing the extrusion process to improve their characteristics. If it's necessary to alter their proportions, fabrication comes next following the heat treatment. You can enhance their look and corrosion resistance by adding a surface finish.

Conclusion

By forcing heated alloy materials via a die, aluminum extrusion is a procedure for producing objects with precise cross-sectional profiles. The shapes can be basic or complex, hollow, solid, or semi-hollow.

Producing items with unique cross-sectional profiles requires the aluminum extrusion technique. It's an exciting process that yields a variety of product shapes that you may heat treat, construct, and polish to your specifications.

For the desired outcome, JMA provides the best aluminum extrusion services. Bring your project to life by getting in touch with them right now.