Low-Pressure Die Casting
Permanent mold, low-pressure die casting uses a reusable steel mold under low pressure to cast various metal shapes. The mold consists of two halves, an upper and lower die, which are precisely machined to form the intricate details of the part. The mold is designed with a gate system to allow the molten aluminum to flow smoothly into the cavity.
The process begins by preheating the permanent mold to a specified temperature to achieve better casting results and fewer defect parts. Once the mold is heated, lubricant is applied to the surface of the die. Depending on the difficulty of the cast, several different layers of lubricant may be needed. Types of casting lubricants include a primer coating to extend intervals between re-application, insulating lubricants to assist with die fill, and release agents to facilitate the removal of the cast.
Afterwards, aluminum alloy in the form of ingots or recycled aluminum is melted in the furnace. The molten metal is poured into a ladle, which is then deposited into the mold cavity through the gating system. Ladle coatings are often applied to extend the life of the ladle. When done correctly, the molten aluminum flows through the die cavity to fill all the intricate spaces within the mold. The low-pressure approach helps with a consistent and controlled fill, reducing the likelihood of air entrapment and ensuring better part surface finish.
Low-pressure die casting allows for precise control to prevent porosity and oxide formation, and ensure parts meet strength and quality standards. Permanent mold aluminum casting is a well suited casting process for simple, symmetrical forms, though more complex parts can also be cast using this method. Low-pressure die casting also requires uncomplicated machinery, making the manufacturing process cost-effective and efficient.
Aluminum permanent mold die casting is widely used by industrial, automotive, aerospace, and electronic industries. Increasing demand for light weight aluminum metals by the automotive sector is contributing to growth for the die casting market in North America.