Process introduction
Die casting is a metal casting process, which is characterized by applying high pressure to the molten metal using the cavity of the mold. Molds are usually processed from higher-strength alloys, and this process is somewhat similar to injection molding. Most die castings are iron-free, such as zinc, copper, aluminum, magnesium, lead, tin and lead-tin alloys and their alloys. Depending on the type of die casting, a cold chamber die casting machine or a hot chamber die casting machine is required.
The cost of casting equipment and molds is high, so the die-casting process is generally only used for mass production of a large number of products. It is relatively easy to manufacture die-cast parts, which generally only requires four main steps, and the individual cost increment is very low. Die casting is particularly suitable for manufacturing a large number of small and medium-sized castings, so die casting is the most widely used one among various casting processes. Compared with other casting technologies, the die-casting surface is flatter and has higher dimensional consistency.
Based on the traditional die-casting process, several improved processes were born, including a non-porous die-casting process that reduces casting defects and eliminates pores. It is mainly used for processing zinc, which can reduce waste and increase the yield of direct injection process. There are also new die-casting processes such as the precision die-casting technology and semi-solid die-casting invented by General Dynamics.
Process characteristics
（1） Wide range of die casting
（2） Castings have high dimensional accuracy and low surface roughness
（3） High productivity
（4） High metal utilization
（5） High casting strength and surface hardness
Pros and cons
Aluminum alloy is much better than zinc alloy in performance. It has good die-casting performance, electrical conductivity and thermal conductivity, and its cutting performance is also good. The disadvantages are also obvious. Aluminum-silicon series alloys are easy to stick to molds, are corrosive to metal crucibles, shrink in volume, and easily produce shrinkage holes.
At the same time, because of their different effects on the mold, the price of the mold used in zinc alloy and aluminum alloy die casting is generally different. Zinc alloy die casting is not easy to stick to the mold and does not corrode the mold, so the price of the mold used in zinc alloy die casting is also It will be cheaper, while zinc alloy die-casting is easy to stick to the mold, corrosive to the metal crucible and other reasons, the mold price required will be higher.
For details, please contact:China Lead Die Casting
