Aluminum suitable for die‑casting is known as die‑cast aluminum, typically an alloy designed for this process. It features advanced core‑pulling and cooling systems. Typically, the material is injected into the mold cavity through a central gate to form the part. How can we understand the key advantages of die‑cast aluminum?

1. Excellent product quality:

Aluminum castings exhibit high dimensional accuracy, typically corresponding to grades 6–7, and in some cases even reaching grade 4. They offer excellent surface finish, generally equivalent to grades 5–8. These castings also possess superior strength and hardness—often 25% to 30% higher than sand‑mold castings—though their elongation is reduced by approximately 70%. They maintain stable dimensions and excellent interchangeability, enabling the production of thin‑walled, complex aluminum components. For instance, zinc‑alloy aluminum castings can now achieve wall thicknesses as low as 0.3 mm, while aluminum alloy castings can reach 0.5 mm; hole diameters in small castings can be as small as 0.7 mm, with minimum spacing down to 0.75 mm.

2. High production efficiency:

Machine productivity is high. For example, a household aluminum die‑casting machine can typically produce 600–700 castings per eight hours, while a small hot‑chamber die‑casting machine can produce 3,000–7,000 castings. Aluminum die‑casting molds have a long service life; a pair of molds for aluminum alloy can withstand hundreds of thousands or even millions of cycles. Mechanization and automation are easily achievable.

3. Excellent economic benefits:

Because aluminum castings are dimensionally accurate, their surfaces are smooth and clean. Typically, they are used directly without further machining, or only require minimal machining, which not only improves material utilization but also reduces the need for machining equipment and labor hours. Castings are cost‑effective, and aluminum castings can be combined with other metallic or nonmetallic materials. This approach saves both assembly time and metal.

Additionally, during aluminum casting, shrinkage cavities and porosity are prone to form. The fundamental principle for aluminum die‑casting manufacturers to prevent these defects is to design an appropriate casting process based on the alloy’s shrinkage and solidification characteristics, ensuring that the casting can establish favorable shrinkage conditions throughout solidification and minimize porosity as much as possible. During solidification, voids and shrinkage cavities may appear; therefore, risers of a specified size are strategically positioned at locations where shrinkage is expected, allowing the shrinkage cavity to be concentrated within the riser, or gating is opened at the solidification front to provide direct feeding. To ensure optimal feeding during solidification, it is essential to control the casting’s solidification direction so that it conforms to either the “directional solidification principle” or the “simultaneous solidification principle.”

The location of the gating system significantly influences the temperature distribution in aluminum castings. By adjusting the pouring temperature and casting speed of the liquid metal, it is possible to promote either directional solidification or simultaneous solidification.

Low-pressure castings feature a dense microstructure, excellent gas tightness, stable dimensional accuracy, and reduced machining requirements, making them well suited for a wide range of sealed, pressure‑bearing components. We offer custom mold development based on your drawings or samples, can tailor the casting process to meet specific operating conditions, and are capable of producing non‑standard, complex‑shaped parts and special‑specification castings to your exact specifications.