Introduction to High Pressure Die Casting

Update:Dec 07 2016

High pressure die casting is a versatile manufacturing […]

High pressure die casting is a versatile manufacturing process in which molten metal is injected with a die casting machine using considerable pressure into a steel mold or die to form products. These molds, or dies, can be used to produce complex shapes with a high level of accuracy and repeatability. Die castings are among the highest volume, mass-produced items manufactured by the metalworking industry. They are used in numerous applications for industries such as automotive, locomotive, agricultural, marine, plumbing, lighting, and many more. The idea of the casting equipment was firstly come up with in 1838 for the consideration producing movable type for the printing industry.

There are several alloys that can be used: zinc, aluminum, magnesium, brass, and copper. Every alloy offers a unique advantage. Let's take a look at a few: Aluminum is one of the commonly used alloys because it is light-weight, very strong, corrosion-resistant, and it easily polished or painted for an appealing finish. Zinc offers high impact strength and is the easiest to cast. Brass is heat-resistant, highly corrosion-resistant and provides excellent electrical conductivity.

High pressure die casting is an efficient, economical process that offers a broader range of shapes within closer tolerances than many other metal manufacturing techniques. They can be produced with smooth or textured surfaces, and they're easily plated or finished with a minimum of surface preparation. They can even be designed to complement the look of a surrounding part.

The mold is important as to produce various sizes. But a die's life is most prominently limited by wear or erosion, which is strongly dependent on the temperature of the molten metal. So do choose the proper metal for the specific dies. What else, it is indeed to operate carefully. Otherwise, the loss would outweigh the gain.

Apart from mold with various sizes, the equipment machines are also important in producing. Basically, there are two major types: hot-chamber machines and cols-chamber machines. The previous one relies on a pool of molten metal to feed the die which equals to the mold. It specifies for the system which include fast cycle times (approximately 15 cycles a minute) and the convenience of melting the metal in the casting machine. And the point that high-melting point metals cannot be utilized and aluminium cannot be used in system should be driven upon much more attentions. However, if some machines include aluminium, zinc alloys with a large composition of aluminium, magnesium and copper and works by firstly melting the material in a separate furnace, a precise amount of molten metal is transported to the cold-chamber machine then.