die casting uk know about gravity die casting - sooperarticles.com

Gravity die casting is the process of pouring liquid metal into a metal mold without any external pressure.The liquid metal enters the cavity of the mold under normal gravity.Gravity die casting is different from high pressure die casting.When high pressure die casting, liquid metal is injected into the metal mold through very high pressure applications, which produces thin-walled castings with much greater dimensional accuracy and surface finish.
With Shell casting and sand casting, the mold must be broken after each casting operation.In the process of being called die casting, the mold known as the mold is made of metal and used a lot of times.Of course, the cost of producing disposable molds is higher.
The most widely used materials in mold manufacturing are heat-resistant alloys of cast iron, steel and iron.For specific purposes, the mold sometimes uses other materials, including copper, graphite and aluminum.Molds can produce castings with smooth surface cleaning and high dimensional accuracy, usually requiring only little or no final processing or other surface treatment.
The service life of the mold depends on factors such as the thermal shock stability of the mold material, the casting material, the pouring temperature and the casting method being used.
There are many details to consider when designing the pattern of the mold.When designing the riser and gate mechanism, it should be remembered that the wall of the mold should apply quenching to the molten metal, so that it will solidify faster than the sand casting.In addition, the mold must set the channel at the joint and at the vent, so that the air of the cast metal replacement can be discharged from the inside of the mold.The mold must also be constructed to not suppress the shrinkage that occurs during metal cooling and solidification, thus allowing the casting to be easily removed.Shrinkage in the design of the core that forms the cavity and groove in the casting may have special problems.Usually, the core is made of steel or special alloy, and sometimes a compressed sand core or shell core is used.
In order to prevent the metal from sticking to the mold, it is possible to use glass as an adhesive and apply chalk, clay or ashes to the interior.This mixture is applied to the mold by soaking, brushing, or spraying.
For simple castings, molten metal can be poured into the open mold from the top.Usually a mold is a closed and complex assembly consisting of two or more parts.It must be designed to make the molten metal flow quickly without hindering each part of the mold.