Extrusion is a process that produces shapes that have an unchanging cross-sectional profile as material is pushed through a die. The materials that are used to form objects in this process, include aluminum, among others. The process creates uniform shapes. When aluminum is pushed through a mold, for example, it takes the shape of the mold, producing custom or stock aluminum extrusions. Complex cross-sections can also be produced through this process.
At Howard Precision Metals, a leader among aluminum extrusion suppliers, we offer our customers with a wide range of aluminum products, which includes aluminum extrusions stock. These shapes are ideal for use in an array application in various industries.
The process of extrusion can actually strengthen aluminum. Extrusions may be created from other materials as well, including stainless steel, other metals, ceramics, plastics, and concrete.
Now, let’s look at direct aluminum extrusion and its advantages and disadvantages.
Direct Aluminum Extrusion
The most common method of extrusion involves the use of the direct aluminum extrusion presses. This method involves the placement of a billet of heated aluminum into a walled container. The aluminum is pressed through the mold (or die) with a ram. This part of the process involves a tremendous amount of pressure, which may be in the range of 100 to 15,000 tons or more. The size of the shape that may be produced through this process is proportional to the pressure capacity of the aluminum press used.
During this step of the process, a dummy block of material is positioned between the heated aluminum billet and the ram in order to prevent these elements from contacting one another. The action of the billet and ram moving forward in the same direction has led to this method being called the forward aluminum extrusion process.
The ram applies pressure, and the aluminum billet is pushed through the hole of the mold. When 6061-T6511 aluminum extrusions stock is manufactured, water quenching is then applied to the hot extruded aluminum profiles. They are then stretched and cut to the desired length. This is the most frequently used method of generating aluminum extrusions.
Advantages of Direct Extrusion
There are a number of advantages to direct extrusion, including:
- Can extrude longer workpieces
- Operational flexibility
- Low cost per component
- Continuous operation
- During hot extrusion, modifications after the process are easy due to the product’s heated condition
- May use various kinds of raw materials
- High production volumes are possible
- Good surface finish
- Good compounding (mixing)
- Cold extrusion produces good mechanical properties
The direct extrusion method is the most common one in use to produce stock aluminum extrusions. This direct extrusion method is simple in nature and allows for the production of more intricate shapes. Despite the need for greater force with this method, its ability to produce more complex shapes is the reason why this method is often preferred during the manufacturing process.
Disadvantages of Direct Extrusion
One of the drawbacks of the direct extrusion process is that the force required to extrude the material (the billet) is greater than what is needed through indirect extrusion. The reason for this is the frictional forces that are introduced as the billet travels through the entire length of the container. The greatest level of force occurs at the beginning of the direct extrusion process and it steadily decreases. The butt end of the billet is not used due to the fact that at the billet’s end the force is increased significantly because of the thin material at this stage and that it flows radially to depart from the die.
Friction, as alluded to above, is an issue with direct extrusions because of the type of motion that occurs between the cylinder walls and heated metal billet. Lubricants may be used to reduce this friction. With direct extrusion, the process is completed quickly, and the cylinder is cooled prior to additional extrusion in order to reduce equipment damage.
A Reliable Source for Your Aluminum Needs
At Howard Precision Metals we know the ins and outs of aluminum as one of the biggest 100% aluminum service centers in the nation. We have more precision high speed saws than any of our competitors. Regardless of the size required, we are capable handling your requirements for stock aluminum extrusions and cutting your aluminum plate. We serve customers in an array of industries with the aluminum skills, resources, and experience our team possesses.
If you are in need of aluminum extrusions, aluminum sheet, or aluminum plate, we are here to help as a trusted source among aluminum extrusion suppliers. Give our team at Howard Precision Metals a call today at 800.444.0311 or send us a request for quote to learn how we can serve you with our aluminum products.
