Product Craft
Aluminum Extrusion is a process used to create objects of a fixed cross-sectional profile. A material is pushed through a die of the desired cross-section. The two main advantages of this process over other manufacturing processes are its ability to create very complex cross-sections, and to work materials that are brittle, because the material only encounters compressive and shear stresses. It also forms parts with an excellent surface finish.
Extruded aluminium with several hollow cavities; T slots allow bars to be joined with special connectors.
Hollow cavities within extruded material cannot be produced using a simple flat extrusion die, because there would be no way to support the center barrier of the die. Instead, the die assumes the shape of a block with depth, beginning first with a shape profile that supports the center section. The die shape then internally changes along its length into the final shape, with the suspended center pieces supported from the back of the die. The material flows around the supports and fuses together to create the desired closed shape. The extrusion process in metals may also increase the strength of the material.
Extrusion of a round blank through a die.Direct extrusion, also known as forward extrusion, is the most common extrusion process. It works by placing the billet in a heavy walled container. The billet is pushed through the die by a ram or screw. There is a reusable dummy block between the ram and the billet to keep them separated.
Capabilities
|
Typical |
Feasible |
|
|
Shapes: |
Flat
Thin-walled: Cylindrical |
Thin-walled: Complex |
|
Part Size: |
Area: Up to 10 mm² |
|
|
Material: |
Metals |
Lead |
|
Surface finish -Ra: |
3.2 - 12.5 μmm |
1.6 - 25.0 μmm |
|
Tolerance: |
± 0.3 mm |
± 0.03 mm |
|
Max wall thickness: |
1 - 15 mm |
0.5 - 25 mm |
|
Advantages: |
Can form complex shapes
High production rate
Good dimensional accuracy
Low labor cost
Short lead time possible |
|
|
Disadvantages: |
Limited to constant part thickness
Lower stress
Hard be welded |
|
|
Applications: |
Brackets, Frame, Heat Sink |
|
