Overview and Basic Principles of Die Casting Molds

Die casting molds are key process equipment that inject molten metal into precision cavities under high pressure, rapidly cool and form high-precision metal parts. This manufacturing process combines the three major technological features of high pressure, high speed, and high temperature, making die-casting technology one of the most efficient and accurate methods in the field of modern metal forming. The quality of die-casting molds directly determines the efficiency of die-casting production, the accuracy of castings, and the mechanical properties of products, playing a core role in component manufacturing in industries such as automotive, electronics, and home appliances.

The basic principle of die-casting technology can be summarized as follows: under the strong pressure provided by the die-casting machine, molten metal fills the mold cavity through the pouring system at a very high speed (usually 30-60m/s), and rapidly cools and solidifies under continuous high pressure (usually 70-350kg/cm ²), ultimately forming a metal part that is consistent with the shape of the mold cavity. During this process, the molten metal completes the filling process in a very short time (usually only 0.01-0.2 seconds), and then crystallizes and solidifies under pressure, thereby obtaining castings with dense structure and precise size. Compared with traditional casting processes, die-casting technology has significant advantages: extremely high production efficiency (able to produce tens to hundreds of pieces per hour), high dimensional accuracy of castings (up to CT4-CT6 levels), good surface quality (Ra1.6-3.2 μ m), and the ability to produce parts with complex shapes and thin walls (as thin as 0.5mm).

From the perspective of mold structure classification, die-casting molds are mainly divided into two categories: hot chamber die-casting molds and cold chamber die-casting molds. Hot chamber die casting molds are suitable for low melting point alloys such as zinc, tin, and lead alloys. Their injection mechanism is directly immersed in the molten metal, which has the advantages of high efficiency and less metal oxidation; Cold chamber die casting molds are used for high melting point alloys (such as aluminum alloys, magnesium alloys, copper alloys), and the metal liquid is supplied to the pressure chamber by a separate furnace, which is more suitable for the production of large and high demand castings. In addition, according to the number of cavities, die-casting molds can also be divided into single cavity molds and multi cavity molds; According to the characteristics of the parting surface, it can be divided into various forms such as horizontal parting molds and vertical parting molds.