[Aluminum extrusion] is to put the aluminum ingot into the extrusion barrel, and apply pressure to the aluminum through the extrusion shaft to make it extruded from the die hole of the given shape and size, produce plastic deformation and obtain the required A processing method for extruded products. The direction of metal flow when pressing is different. Extrusion can be divided into forward extrusion, reverse extrusion and joint extrusion.

During forward extrusion, the movement direction of the extrusion shaft is the same as the flow direction of the extruded metal, and when reverse extrusion, the movement direction of the extrusion shaft is opposite to the flow direction of the extruded metal. According to the heating temperature of the billet, extrusion can be divided into hot extrusion and cold extrusion. In hot extrusion, the ingot is heated to the recrystallization temperature for extrusion, and cold extrusion is performed at room temperature.