Extrusion temperature and extrusion speed are two basic parameters in the extrusion process of aluminum profiles. The temperature in the plastic deformation zone must be appropriate to the best temperature range for metal plasticity.
The greater the flow speed of the metal, the smaller the heat absorbed by the surrounding medium, the higher the temperature in the plastic deformation zone, and vice versa. Under a certain degree of deformation, or choose the appropriate preheating temperature, or choose the appropriate deformation speed, the temperature of the plastic deformation zone can be kept within the specified range, when the deformation speed is small, the preheating temperature must be increased. When the deformation speed is large, the preheating temperature must be reduced, so a higher extrusion speed can be obtained by using the method of "cone" heating and cooling the mold;
With the change of extrusion conditions, the extrusion temperature and extrusion processing speed in the extrusion process are constantly changing.
When extruding aluminum alloy, the extrusion temperature is low (400-500 ° C), the extrusion speed is very slow (≤25mm/s), and the thermal conductivity of aluminum alloy is very high, so the temperature change caused by the heat conduction of the extruded metal and the heat exchange between the metal and the extrusion tool must be considered when calculating the temperature field of the plastic deformation zone.
The temperature rise in the aluminum extrusion process has a certain impact on the temperature of the tool and the size of the extrusion pressure, so this factor should be fully considered when designing and using the extrusion die.
