1. BSc in Mechanical Engineering
Project Title:
EXPERIMENTAL INVESTIGATION OF THE PERFORMANCE OF
COATED DIES WITH DIFFERENT GEOMETRIES
AFTER HOT AND COLD EXTRUSION OF ALUMINUM
Submitted by:
GEORGE GEORGIOU
Supervisor: Dr.-Eng. Antonios Lontos
NICOSIA, 12/01/2017

2. TABLE OF CONTENTS
1. INTRODUCTION
2. HOT EXTRUSION EXPERIMENTAL PROCEDURE
3. COLD EXTRUSION EXPERIMENTAL PROCEDURE
4. CONCLUSIONS

3. 1. INTRODUCTION
Coating Material
Hardness (HV pl)
Aluspeed
3200
Supernitride (SN)
2600
DLC
2500

4. Extrusion equipment - Pressing Load Measurement

5. Aluminum billets (AA6061)

6. Hot extrusion – aluminum product roughness
2. HOT EXTRUSION EXPERIMENTAL PROCEDURE
Hot extrusion – aluminum product roughness

7. Billets for Billets for cold extrusion hot extrusion
3. COLD EXTRUSION EXPERIMENTAL PROCEDURE
Billets for
cold extrusion
Billets for
hot extrusion
Cold extrusion tests

8. Pressing load and mandrel movement

9. Dies and products after cold extrusion

10. Experimental results after cold extrusion

11. 4. CONCLUSIONS
Dies with no coating demonstrate earlier and worst damage. The critical area that was damaged is the circumference of the hole.
For the same case the uncoated die with 8o extrusion angle appear better performance and better quality roughness of the extruded aluminum.
The best behavior from all the applied coating types was demonstrated from the aluspeed coating.
The coated dies with the supernitride and DLC coatings, in the beginning of the experiments appear to have a good behavior. After a number of tests both coatings were slightly detached from the inside area oh the hole. Probably the geometry of the dies prevents the good coating adhesion with the material of the dies.

12. FUTURE WORK
New and more suitable coatings will be investigated on extrusion dies.
Further simulations and research for most promising die geometry.
Large scale of extrusion tests with various coated dies and new geometries.
The simulating and experimental work will expand to other processes such as forging, drawing, casting, punching and polymer processing.

13. Thank You
for your attention