Extrusion

Question 1

What are Extrusions used for?

Answer 1

Making profiles w/ wide variety of shapes (can be solid or hollow)
Tight tolerances
Mostly made of Aluminum

Question 2

Extrusion Process

Answer 2

1. Preheated billet (cylindrical bars made w/ casting) placed in press container
2. Pressed by a ram through an extrusion die
3. Extruded shape comes out of die
4. flow of metal similar to fluid flow from large channel to smaller one

Question 3

Extrusion Ratio =

Answer 3

Cross-section ratio of:
(billet/profile

Question 4

Temperature Taper

Answer 4

Only used sometimes
1.Die end is hotter than ram end

Question 5

Die

Answer 5

Flat disk made of tool steel

Question 6

Hollows

Answer 6

Created with solid billets using multipart dies

Question 7

Metals Used(6)

Answer 7

1.6000 series Alloys - high exit speeds
2.7000 Series alloys - low exit speeds
3.Copper - High T
4.Brass - High T
5.Carbon Steel(rare)
6. Magnesium(rare)

Question 8

Other extrusion methods

Answer 8

1. Indirect Extrusion
   Uses hollow ram
   extrusion emerges through ram
2. Hydrostatic extrusion
   Fluid placed b/w ram & billet
   eliminates friction

Question 9

What does Extrusion Diagram represent

Answer 9

Max Velocity that material can be extruded v. initial billet temp
Overall shows viable combinations of initial temp and exit velocity
Ignore Temperature Taper