High productivity has been demand of the extrusion process to obtain excellent quality such as more constant shape accuracy, more uniform mechanical strength, more excellent secondary fabrication properties and high surface. These properties of extruded section depend on the microstructure of the aluminum alloy. In order to keep them constant throughout the entire length the extruded section, it is necessary to keep a constant temperature of an extruded section in the bearing zone of the dies because the microstructure changes with temperature during plastic formation. It is called as isothermal extrusion.

Over the past few decades, many studies have been conducted on isothermal extrusion. Using pyrometer system of non-contact measuring temperature with high speed motion, and the results of finite element method (FEM) analysis, isothermal extrusion has been realized in the extrusion of A6063 with uniform temperature billet in our extrusion lines by our technicians. We control the exit temperature at 530±5℃.