Extrusion Flashcards
1
Q
What are Extrusions used for?
A
Making profiles w/ wide variety of shapes (can be solid or hollow)
Tight tolerances
Mostly made of Aluminum
2
Q
Extrusion Process
A
- Preheated billet (cylindrical bars made w/ casting) placed in press container
- Pressed by a ram through an extrusion die
- Extruded shape comes out of die
- flow of metal similar to fluid flow from large channel to smaller one
3
Q
Extrusion Ratio =
A
Cross-section ratio of:
(billet/profile
4
Q
Temperature Taper
A
Only used sometimes
1.Die end is hotter than ram end
5
Q
Die
A
Flat disk made of tool steel
6
Q
Hollows
A
Created with solid billets using multipart dies
7
Q
Metals Used(6)
A
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)
8
Q
Other extrusion methods
A
- Indirect Extrusion
Uses hollow ram
extrusion emerges through ram - Hydrostatic extrusion
Fluid placed b/w ram & billet
eliminates friction
9
Q
What does Extrusion Diagram represent
A
Max Velocity that material can be extruded v. initial billet temp
Overall shows viable combinations of initial temp and exit velocity
Ignore Temperature Taper
