1/13 EXPERIMENTAL INVESTIGATION OF THE PERFORMANCE OF COATED DIES WITH DIFFERENT GEOMETRIES AFTER HOT AND COLD EXTRUSION OF ALUMINUM BSc in Mechanical Engineering PROJECT TITLE: Submitted by: GEORGE GEORGIOU Supervisor: Dr.-Eng. Antonios Lontos NICOSIA, 12/09/2014

2/13 1. INTRODUCTION 2. HOT EXTRUSION EXPERIMENTAL PROCEDURE 3. COLD EXTRUSION EXPERIMENTAL PROCEDURE 4. CONCLUSIONS TABLE OF CONTENTS

3/13 1. INTRODUCTION Coating MaterialHardness (HV pl) Aluspeed3200 Supernitride (SN)2600 DLC2500

4/13 Extrusion equipment - Pressing Load Measurement

5/13 Aluminum billets (AA6061)

6/13 Hot extrusion – aluminum product roughness 2. HOT EXTRUSION EXPERIMENTAL PROCEDURE

7/13 Cold extrusion tests Billets for cold extrusion Billets for hot extrusion 3. COLD EXTRUSION EXPERIMENTAL PROCEDURE

8/13 Pressing load and mandrel movement

9/13 Dies and products after cold extrusion

10/13 Experimental results after cold extrusion

11/13 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 8 o 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. 4. CONCLUSIONS

12/13 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. FUTURE WORK

13/13 Thank You for your attention