Definition of aluminum billet
Aluminum billet is a type of aluminum ingot that is mostly used in extrusion industries. Aluminum billet is one of the semi-finished products of aluminum casting. Aluminum billet is made according to customer’s opinion and order in various alloys according to international standards and in different sizes. The continuous casting process is a method that is used today to produce aluminum extrusion billets. In this method, molten aluminum is poured into a round mold that has a small depth. These molds usually have a round surface that when the material starts to freeze Melted in the lower part of the mold starts to go down at a suitable speed. Water is sprayed on the freshly frozen surface of the aluminum billet when it comes out of the mold. Different billets require different mold sizes.
Types of billet aluminum
– Standard billet
– Import billet
– Billet DC
– Remelting or conversion billet
What are the advantages of the DC casting method compared to other methods?
– Phase separation in this method is minimal.
– This method has the ability of large billets.
– Low amount of cracks in high strength alloys.
– In order to avoid problems with the transfer of molten materials, it is carried out smoothly and smoothly at a low temperature.
DC method for aluminum billet production and its advantages
In the DC method, after the metals are placed in the desired mold and their initial shape is determined, they are cooled slowly under certain conditions. This method is more suitable for metals with shallow depth. In this method, when the lower layer of the metal becomes cold and hard, it is separated from the frame little by little. In the next step, water is poured on the upper surface to perform the freezing operation with high quality and fast. Now, here are the advantages of this method:
– Fast separation of metal from the mold
– Producing billets of different sizes
– greatly reducing the amount of cracks on or inside the alloys
– Using low temperature to produce aluminum billet
– The operation is carried out in a regular and smooth manner without risk and additional risk.
What are the variables of aluminum billet casting?
Below we explain the variables of aluminum billet casting:
– What should be the pouring temperature? To prevent gas accumulation and oxide formation, the temperature of the molten metal should be as low as possible. Research has shown that the mechanical properties of water-quenched billets are much higher than air-cooled billets.
– What is the casting speed? Decreasing the cooling speed increases the precipitation in the solid solution, and on the other hand, rapid cooling shows the opposite results.
– What type of template should it be? The type of material determines the type of mold. Mold recognition requires knowing parameters such as proper gloss, machinability, workability, and temperature.
– What is the speed of the water flow? During casting, the temperature and speed of the water flow should be adjusted so that the water wets the entire surface of the aluminum and flows in a cascade on its surface, the water should not be allowed to jump on the surface of the aluminum.
Three stages of aluminum billet homogenization:
The homogenization of billets consists of three steps, which are: heating the aluminum billet at a certain speed, placing it at a suitable temperature for a certain period of time and cooling it at a suitable speed during the homogenization period. The billets are kept at a high temperature for a certain period of time, that’s why the penetration is increased and the slopes are reduced. Therefore, the controlling factor in the homogenization of an alloy is the permeability of the alloy elements present at the homogenization temperature. The higher the homogenization temperature, the faster and more industrially effective the aluminum billet homogenization.
