After the casting process, the billets must also go through the heat treatment process. The purpose of the heat treatment is to assure optimal mechanical characteristics for further plastic deformation (extrusion of the billets).

Heat treatment in a continuously fed furnace first slowly heats up and than hold extrusion ingots on the temperature approximately 575°C. After cooling the extrusion ingots move further to the air-cooling chamber.

The homogenising furnace is a closed chamber, heated with the natural gas. A special processing computer ensures proper heating and cooling of individual alloy types. Homogenising parameters are dependent on alloy and diameter.

Cooled extrusion ingots are cut with a saw on both ends. An automatic layer takes off the billets and places them on wooden palettes and cords them with strips into bonds, which are then prepared for transport.

Structure processes during heat treatment:

• Create small and finely dispersed Mg2Si particles
• Reduce the micro-segregation
• Remove tension in cast material
• Phase transformation of needle AlFeSi to globular AlFeSi
• Control the distribution of dispersions in alloys containing Mn, Cr and Zr.