Business Negotiations DFM Meeting Molds Machining Precision Machining Shop The metal materials used in die casting are mainly aluminum alloys, magnesium alloys, zinc alloys and copper alloys. Since aluminum alloy die castings are widely used in the automotive industry, they account for a high proportion of die castings. According to the statistics of China Foundry Association, the proportion...
SIPX provides superior quality die casting parts and components for a wide range of industries including automotive, food dairy, machinery, medical, plumbing, watering, mining, petrochemical, electrical, energy, aerospace, submarine and others.
Our die casting machines range from 180 up to 2,000 metric tons, we can produce die casting parts from a few grams to more than 50kg with superior quality. For die casting parts with requirements of esthetical, functional, or protective coatings, we also offer a broad range of surface finishing including powder coating, e-coating, shot blasting, chrome plating, and bright finish.
What is Die Casting
Die casting is a metal casting process that is characterized by forcing molten metal under high pressure into a mould cavity. The mold cavity is created using two hardened tool steel dies which have been machined into shape and work similarly to an injection mold during the process. Most die castings are made from non-ferrous metals, specifically zinc, copper, aluminium, magnesium, lead, pewter, and tin-based alloys. Depending on the type of metal being cast, a hot- or cold-chamber machine is used.
Usually, alloys with a low melting point are used. This casting process is particularly suitable for series and mass production of components because, unlike sand casting, for example, permanent metal molds are used which do not have to be destroyed after casting. It is possible to produce large and complex components with low wall thicknesses.
Die castings are characterized by a very good surface finish (by casting standards) and dimensional consistency.
How Are Die Castings Made?
Hot-chamber die casting
Hot chamber machines are used for alloys with low melting temperatures, such as zinc, tin, and lead. The temperatures required to melt other alloys would damage the pump, which is in direct contact with the molten metal. The metal is contained in an open holding pot which is placed into a furnace, where it is melted to the necessary temperature. The molten metal then flows into a shot chamber through an inlet and a plunger, powered by hydraulic pressure, forces the molten metal through a gooseneck channel and into the die. After the molten metal has been injected into the die cavity, the plunger remains down, holding the pressure while the casting solidifies. After solidification, the hydraulic system retracts the plunger and the part can be ejected by the clamping unit.
Cold-chamber die casting
Cold chamber machines are used for alloys with high melting temperatures that can not be cast in hot chamber machines because they would damage the pumping system. Such alloys include aluminum, brass, and magnesium. The molten metal is still contained in an open holding pot which is placed into a furnace, where it is melted to the necessary temperature. However, this holding pot is kept separate from the die casting machine and the molten metal is ladled from the pot for each casting, rather than being pumped. The metal is poured from the ladle into the shot chamber through a pouring hole. The injection system in a cold chamber machine functions similarly to that of a hot chamber machine, however it is usually oriented horizontally and does not include a gooseneck channel. A plunger, powered by hydraulic pressure, forces the molten metal through the shot chamber and into the injection sleeve in the die. After the molten metal has been injected into the die cavity, the plunger remains forward, holding the pressure while the casting solidifies. After solidification, the hydraulic system retracts the plunger and the part can be ejected by the clamping unit.