seamless aluminium coils and combination die extrusion aluminium coils

What is the difference between seamless aluminium coils and combination die extrusion aluminium coils?

Most of the aluminium coils on the market are produced using the conventional combination die welding and extrusion process, which cannot completely avoid welding lines, especially after oxidation, which is easy to have dark lines. Extrusion production using high temperature, slow speed extrusion process, especially to control the "three temperature", aluminum coil, extrusion barrel, and die to keep clean, aging time and temperature according to the thickness and size of the aluminum coil to make appropriate adjustments can be.

The current use of aluminium coil extrusion machine including extrusion box and cylinder, will be heated aluminum block from the inlet into the extrusion box, the cylinder began to work so that the extrusion beam to push the aluminum block towards the extrusion die to move, high temperature state of the aluminum block has good plasticity, when the aluminum block temperature is reduced plasticity will also be reduced, in the extrusion beam under a certain pressure and speed, the extrusion pad to push the aluminum block to produce plastic flow from the extrusion die extrusion, so as to In the extrusion process, the aluminium block is under strong pressure in the extrusion deformation zone, which can give full play to its plasticity and obtain a large deformation, while the extrusion deformation can improve the organisation of the metal material and enhance its mechanical properties, especially for the aluminium block with extrusion effect, its extrusion products in the quenching and aging, the longitudinal (extrusion direction) mechanical properties are much higher than other processing Extrusion processing also has great flexibility, only need to replace the extrusion die can be produced on the same equipment shape, size and specifications and varieties of different products, and the replacement of extrusion die operation is simple and convenient, time-consuming small, high efficiency. However, there are still major problems with the forming of some double-layer seamless aluminium coils. Therefore, it is necessary to improve this situation.