Gold Ingot

Gold Ingots are manufactured by the freezing of a molten liquid in a mould. To manufacture gold ingots there are several steps. First, the mould makes the melt solid completely. Next, the shape and size of the mould is made to make it easier to handle the ingot and the processing. Lastly, the mould is created to help cut down on melt wastage and help in the removal of the gold ingot.

There are many designs which helps with the physical properties of the liquid melt and the solidification process. There may be molds that allow top, horizontal or bottom-up pouring and may have walls that are fluted or flat. The fluted design increases heat transfer owing to a larger contact area. Ingot moulds are desgined to be tapered so that it will not allow the formation of cracks due to uneven cooling. If gold ingots have crack defects, they will be of no use and will have to be re melted, recycled or thrown away.

To determine the crystalline material, the way the ingot is cooled and the precipitation of the metal determines the the physical structure of the ingot. When the metal comes into contact with the ingot walls in the pouring process, the metal is cooled quickly and forms into either a columnar structure, or what is called a "chill zone" of equiaxed dendrites. This depends on how the liquid is cooled and the cooling time of the mould.

The top poured ingot has a different volume effect when it cools, which causes the top of the liquid to have a curved surface at the mould top. This curve may have to be removed by a machine. The mould has several zones that may effect the cooling rate of the metal. Near the wall is a solid zone that takes the heat away from the melt that is beind solidify. There is also something called the "mushy zone" for alloys and this is the result of solid-liquid equilibrium regions in the alloy's phase diagram and a liquid region. The rate of the front advancement determines and controls how long it will take for the dendrites or nuclei form into a solid withing the region. By turning the properties of the heat transfer of the mold, the width can controlled while the metal is in the mushy zone. Also, the liquid melt alloy compositions can be adjusted to get the desired effect.

There are continuous casting methods for gold ingot processing that allows a stationary front of solidification to form by the continual take-off of cooled solid material, in turn adds an additional molten liquid to the to the process of the casting method.

As you can see, there are many different methods in creating the gold ingot and many steps that are taken to ensure the perfect gold ingot. To find out more about ingot gold and how you can buy, sell or make a profit from it, click on the link below. Gold Ingot
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