Die Casting

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.

Why Choose SIPX

With over 10 years of experience, Sipx is well versed in this field. Yes, you are dealing with masters. You can trust us with your needs and expectations.

You will save 20-30% of the cost because of our excellent production capacity. Furthermore, we only insist on making high-quality casting products.

  • Rapid Prototyping
  • One-Stop Services Supplier, On-demand manufacturing
  • ISO16949 Certificated
  • Strict Quality Control System

    *Your details will be kept strictly confidential with us.

    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.

    die casting process-clamping

    1. Clamping

    The first step is the preparation and clamping of the two halves of the die. Each die half is first cleaned from the previous injection and then lubricated to facilitate the ejection of the next part.

    die casting process-injection

    2. Injection

    The molten metal, which is maintained at a set temperature in the furnace, is next transferred into a chamber where it can be injected into the die. The method of transferring the molten metal is dependent upon the type of die casting machine.

    die casting process-cooling

    3. Cooling

    The molten metal will begin to cool and solidify once it enters the die cavity. When the entire cavity is filled and the molten metal solidifies, the final shape of the casting is formed.

    die casting process-ejection

    4. Ejection

    After the predetermined cooling time has passed, the die halves can be opened and an ejection mechanism can push the casting out of the die cavity.

    5. Trimming

    During cooling, the material in the channels of the die will solidify attached to the casting. This excess material, along with any flash that has occurred, must be trimmed from the casting either manually via cutting or sawing, or using a trimming press.

    Advantages of Die Casting

    If you are reading this discussion on sand casting processes, you are likely trying to get a better idea of what method of prototype casting would be best for the product that you have in mind. Prototype casting using a sand casting foundry is best when you might need:

    • Simple or complex shapes
    • High rates of production
    • Corrosion resistance
    • Monolithic – combine multiple functions in one
    • Efficient and economical alternative to other processes
    • Thin wall thickness – up to 0.040 inches for small castings
    • Light weight – light alloys are used
    • Corrosion resistance – surfaces are smoother than other casting types

    Materials

    Die casting typically makes use of non-ferrous alloys. The most common alloys that are die cast are shown below, along with brief descriptions of their properties.

    Material Tensile Strength (Mpa) Thermal Conductivity (W/mK) Features
    Aluminum A380 325 96 Best combination of mechanical, casting, and the thermal properties.
    Excellent fluidity, pressure tightness, and resistance to hot cracking.
    Widely used for engine brackets, hand tools, electronic equipment chassis, gearbox cases, and household furniture.
    Aluminum A360 317 113 Excellent pressure tightness and fluidity.
    High corrosion resistance.
    High strength in elevated temperatures.
    Aluminum 413 295 121 Good combination of casting, mechanical, and thermal properties.
    Excellent fluidity, pressure tightness, and resistance to hot cracking.
    Aluminum 383 310 96 Often used for highly intricate components.
    Good corrosion resistance, lightweight.
    Good combination of casting, mechanical, and dimension stability.
    Aluminum B390 317 134 High hardness and good wear resistance.
    Suitable for internal combustion engine pistons, cylinder bodies for compressors, and brakes.
    Aluminum A413 290 121 Excellent pressure tightness.
    Good choice for hydraulic cylinders.
    Suitable for die casting intricate components.