Hot Chamber Zinc Castings 800 degrees Fahrenheit. The most ideal machine used in zinc die casting is the hot chamber. Hot chamber zinc casting is the common method used in zinc because it does not require a very high temperature in order to melt the metal. Metals with high-melting point such as aluminum do not do well in hot chamber casting. There is a tendency that the metal will absorb the iron in the machine. Hot chamber die casting is used in other alloys that have low-melting point such as copper and magnesium.
The process in hot chamber zinc die casting begins with melting the slabs of zinc in the furnace. In order for zinc to reach its melting point, heat must be approximately 700-800 degrees Fahrenheit. As soon as the zinc reaches its melting point and turns liquid, it is then displaced through a shot sleeve. Known as the goose’s neck, the sleeve is dipped in the furnace and then injected into the die. Pressure is applied until the zinc returns to its solid state while retaining the shape of the die cast. To make the casting process easier, lubricants are applied to the mold. This helps the removal of the molded zinc as well as the control of the temperature easier. In some instances, robotics is employed to remove the molded metal. The solidification process usually takes 2-15 seconds.
Other operations after the hot chamber zinc casting are performed to polish the molded metal. Such operations include trimming, painting and plating. This makes the details of the casted zinc more precise and functional.