Die casting process is a process of unifying pressure, speed and time with three elements: machine, mold and alloy. When used in metal hot working, the existence of pressure is the main feature that distinguishes the die casting process from other casting methods. Pressure casting is a special casting method with small cutting amount and rapid development in modern metalworking technology. It is a process that molten metal is filled into a mold at high pressure and high speed, and crystallized and solidified at high pressure to form a casting. High pressure and high speed are the main characteristics of pressure casting. The common pressure is several tens of MPa, the filling speed (inner gate speed) is about 16 ~ 80m/s, and the time for filling the cavity with molten metal is very short, about 0.0 1 ~ 0.2 seconds. Because the products produced by this method have the advantages of high production efficiency, simple process, high tolerance grade of castings, good surface roughness and high mechanical strength, it can save a lot of machining procedures and equipment and save raw materials, so it has become an important part of China's foundry industry.

Die-casting technology is a process that combines die-casting machine, die-casting die and alloy organically and comprehensively. The process of filling the cavity with metal in die casting is a unified process of pressure, speed, temperature, time and other technological factors. At the same time, these technical factors influence, restrict and complement each other. Only by correctly selecting and adjusting these factors and making them coordinate with each other can we achieve the expected results. Therefore, in the process of die casting, we should not only pay attention to the manufacturability of casting structure, the advancement of die casting mold, the excellent performance and structure of die casting machine, the adaptability of die casting alloy selection and the standardization of melting process; Attention should be paid to the important role of process parameters such as pressure, temperature and time in casting quality. In the process of die casting, we should pay attention to the effective control of these parameters.