The principle of die casting is to use high pressure to quickly inject molten metal into the cavity of a precision metal mold, and then cool and solidify under high pressure to form a casting.
The die casting process uses the mold cavity to apply high pressure to the molten metal. The mold is usually made of a stronger alloy. This process is similar to injection molding.
The operation technology of die casting mainly includes the following steps:
Prepare the molten metal: Heat the metal to a molten state.
Fill the mold: Fill the molten metal into the mold cavity under high pressure and high speed. The commonly used pressure is tens of MPa, the filling speed is about 16 to 80 m/s, and the time for the molten metal to fill the mold cavity is extremely short, about 0.01 to 0.2 seconds.
Cooling and solidification: The molten metal cools and solidifies under high pressure in the mold to form a casting.
Open the mold and take out the casting: After the casting solidifies, open the mold to take out the casting to complete a die casting cycle.
The classification of die casting mainly includes two methods: cold chamber die casting and hot chamber die casting:
Cold chamber die casting: The molten metal is poured into the die chamber by manual or automatic pouring device, and then the die-shot punch moves forward to press the metal into the mold cavity.
Hot chamber die casting: The molten metal automatically flows into the die chamber through the feed port on the die chamber, and the die-shot punch moves downward to push the molten metal into the mold cavity through the gooseneck tube.
The application field of die casting is very wide, especially suitable for manufacturing a large number of small and medium-sized castings. Due to its flat surface, high dimensional consistency and high production efficiency, die casting is the most widely used one among various casting processes. In addition, the die casting process has also derived a variety of improved processes, such as non-porous die casting, direct injection process, precision and high-speed die casting technology, etc., which further improve the casting quality and production efficiency.
