Alloy die casting is a metal casting process characterized by the use of a mold to apply high pressure to the molten metal. The mold is usually made of a stronger alloy, a process somewhat similar to injection molding. Most die-cast castings are iron-free, such as zinc, copper, aluminum, magnesium, lead, tin, lead-tin alloys and their alloys. Depending on the type of die casting, it is necessary to use a cold chamber die casting machine or a hot chamber die casting machine.

Alloy die-casting equipment and molds have high costs, so the die-casting process is generally only used for mass production of a large number of products. Manufacturing die castings is relatively easy, generally only four main steps are required, and the individual cost increment is very low. Die casting is especially suitable for manufacturing a large number of small and medium-sized castings, so die casting is one of the widely used casting processes. Compared to other casting processes, die-casting has a smoother surface and higher dimensional consistency.

The traditional alloy die casting process mainly consists of four steps, including mold making, molding, injection and sand fallout, which are also the basis for various improved die casting processes. During preparation, lubricant is sprayed into the mold cavity. Lubricants can not only help control the temperature of the mold, but also help the casting to be demolded. The mold can then be closed and the molten metal can be injected into the mold at a high pressure of approximately 10 to 175 MPa. When the molten metal is filled, the pressure will be maintained until the casting solidifies, and then the pusher pushes out all the castings. Since there may be multiple cavities in a mold, multiple castings may be produced in each casting process. During the falling process, residues including dies, runners, gates and flashes need to be separated, usually by extruding castings with special trimming dies.

High-pressure injection results in a very fast mold filling speed, so the molten metal can fill the entire mold before any part solidifies. In this way, even thin-walled parts that are difficult to fill can avoid surface discontinuities. But this also leads to air entrapment, as it is difficult for air to escape when filling the mold quickly. This problem can be reduced by placing the exhaust port on the parting line, but even very delicate processes can leave pores in the center of the casting. Most die casting can complete some structures that cannot be completed by casting, such as drilling, polishing, etc.

After sanding, you can inspect for defects, common defects include stagnant current and cold scars. These defects can be caused by insufficient mold or molten metal temperature, metal mixed with impurities, too few vent holes, too much lubricant, etc., other defects include pores, shrinkage holes, hot cracks, and flow marks. So far, the overall marketing level of China's alloy die-casting enterprises is still in the initial stage of the world, without brand building, without technological innovation capabilities, let alone control the industrial chain. For China's alloy die-casting industry, only by changing concepts, innovating and developing, and adjusting the industrial structure can we gradually get out of the predicament and make China's die-casting industry develop better.