Transfer and pouring of molten aluminium discs

Transfer and pouring of molten aluminium discs

We know that aluminium alloys are solid, so what should we do when manufacturing aluminium alloy products of different shapes? Do we have to beat the solid aluminium alloy into a disc like iron? The answer is no. We have to melt the aluminium ingot into a liquid first and then pour it. Let's take a look at the transfer and pouring of aluminium discs!

Although the density of solid aluminium oxide approximates that of the aluminium melt, it takes a long enough time to sink to the bottom of the crucible after it has entered the interior of the melt. The aluminium oxide film formed after the molten aluminium disc is oxidised, but only the side in contact with the molten aluminium is dense, and the side in contact with the air is loose and has a large number of small holes with a diameter of 60 - 100 A. Its surface area is large, strong adsorption, very easy to adsorb in the water vapour, and has a tendency to float upwards. Therefore, in this oxide film and aluminum melt specific gravity difference is small, will be mixed into the melt, floating and sinking very slowly, it is difficult to exclude from the melt, the formation of pores in the casting too entrapment. Therefore, the key in transferring aluminium disc melt is to minimise the stirring of the molten metal and to minimise the contact between the melt and the air.

When using the tilting crucible to transfer the melt, in order to avoid the mixing of melt and air, the pouring pack should be placed as close as possible to the furnace nozzle and tilted so that the melt flows down the side wall of the pouring pack and does not directly impact the bottom of the pack and churning and splashing occur.

The use of correct and reasonable pouring method is one of the important conditions for obtaining high quality aluminium disc castings. Production practice, pay attention to the following matters, to prevent, reduce casting defects is very effective.