Process Characteristics:

(1) Metal or alloy liquid is filled into the mold under high pressure and crystallized and solidified at a certain pressure, usually ranging from several megapascals to several tens of megapascals, up to 200MPa. This ensures high quality, excellent mechanical properties, and good airtightness of the castings.

(2) The metal or alloy liquid fills the mold at a fast speed, with injection speeds usually between 10-30m/s, reaching up to 80m/s. This results in very short casting and molding times (0.001-0.2s), leading to high productivity.

(3) The mold has a large heat capacity and rapid heat conduction, resulting in dense casting structures, fine crystallization, excellent mechanical properties, and good wear and corrosion resistance.

(4) Due to the above characteristics, metal or alloy liquids can be die-cast at relatively low temperatures, even with semi-liquid fluids, producing castings with thin walls and complex shapes.

Advantages:

(1) High dimensional and shape precision of die-castings. The precision of non-ferrous alloy die-castings can generally reach IT11~IT14 levels according to GB 1800-70, with some reaching IT9 levels, ensuring excellent interchangeability.

(2) Smooth surface of die-castings, with surface roughness reaching Ra0.80~0.4um according to GB/T 1031-83, and a maximum of Ra0.21m.

(3) Die-casting can produce thin-walled (as thin as 0.3mm), deep-cavity, complex structures with small holes (minimum diameter of 0.7mm), threads (minimum pitch of 0.75mm), patterns, text, and castings with various materials.

(4) Die-casting can produce castings with embedded parts of different shapes, sizes, and materials, saving precious metals, reducing processing time, meeting diverse requirements, expanding product applications, and simplifying manufacturing processes.

(5) Due to the short filling time and rapid cooling and solidification under high pressure, die-castings have dense structures, fine surface layers, high tensile strength (25%~30% higher than sand castings), good hardness, wear resistance, and corrosion resistance.

(6) High material utilization. Die-castings, with high dimensional accuracy and low Ra values, usually require little or no additional processing after molding, resulting in high material utilization (up to 80-95%) and simplified manufacturing processes.

(7) High productivity. Modern die-casting operations are highly mechanized and automated, leading to short production cycles and high efficiency, making it suitable for mass production.

(8) Long die life. Advanced die materials and efficient strengthening methods significantly extend die life, with lifespans reaching hundreds of thousands to over a million castings.

Disadvantages:

(1) Die-castings may have bubbles or porosity when using conventional die-casting processes. Impurities and gases not refined in the metal liquid can lead to issues if heat treatment for strengthening is applied. Vacuum melting and vacuum die-casting are required for die-castings that need heat treatment.

(2) Weight and size limitations are imposed by the die-casting machine and mold manufacturing conditions, posing challenges for complex-shaped castings with internal structures.

(3) Limited alloy types suitable for die-casting. The poor high-temperature performance of die-casting molds and restrictions on working temperatures limit the use of high-melting-point metals, such as cast iron, carbon steel, alloy steel, stainless steel, etc.

(4) Not suitable for small-batch production. The high cost of die-casting machines and supporting equipment, long design and manufacturing cycles for dies, and high single-piece production costs make it uneconomical for small-batch production.