Gravity Die Casting

Gravity die casting is a process that uses a reusable metal mold or die to produce metal parts. In this process, molten metal is poured into a pre-designed mold or die, solidifying it into the desired shape as the metal cools. 

Gravity die casting is commonly used to produce small to medium-sized parts with complex shapes, such as engine components, pump parts, and gears. The process offers several advantages over other casting methods, including high production efficiency, good dimensional accuracy, and excellent surface finish.

Difference between gravity die casting and die casting

Unlike die casting, gravity die casting uses gravity to fill the mold cavity, while die casting uses high pressure. The molten metal is poured from a ladle into the mold. While die casting is often used to produce large quantities of parts quickly and efficiently; gravity die casting is more suitable for smaller production runs and is typically better for producing parts with higher dimensional accuracy and surface finish.

Advantages of gravity die casting

Gravity die casting is a versatile and reliable process offering many advantages over other methods. It is well-suited for producing small to medium-sized parts with complex geometries and high-quality requirements. Some of its benefits include: 

• High dimensional accuracy: The process produces parts with excellent dimensional accuracy and very tight tolerances due to the absence of external pressure during the casting process.
• Good surface finish: Gravity die casting produces parts with a smooth surface finish, reducing the need for additional finishing processes such as polishing or grinding.
• Design flexibility: The process can produce parts with complex geometries and thin walls, making it ideal for a wide range of applications in various industries. 
• Excellent mechanical properties: Gravity die cast parts typically offer excellent mechanical properties such as high durability and strength.

Gravity die casting molds

The mold is a critical component of the gravity die casting process, and its design and construction play a critical role in determining the quality and accuracy of the finished product. Proper mold design, construction, and maintenance are essential to producing high-quality parts consistently and efficiently. 

The mold is usually made in two halves, clamped together during the casting process. It is reusable, making it very cost-effective. The mold cavity is designed to create the desired shape of the finished product and can be customized to produce parts with complex geometries and intricate details. It is typically made of a heat-resistant material to withstand the high temperatures of the molten metal poured into the mold. One material that is ideal for gravity die casting molds is high conductivity copper alloys.

High Conductivity Copper Alloys in Gravity Die Casting

High conductivity copper alloys, like AMPCOLOY® 83, AMPCOLOY® 88, AMPCOLOY® 95, AMPCOLOY® 940, and AMPCOLOY® 944, are preferred materials for gravity die casting molds due to their exceptional combination of strength, durability, and thermal conductivity. These copper alloys are known for their superior mechanical properties and resistance to wear and corrosion, making them an ideal choice for high productivity in die casting molds.

The utilization of high conductivity copper alloys in gravity die casting allows for the production of premium-quality parts capable of enduring a broad range of environmental conditions and mechanical stresses. Consequently, high conductivity copper alloys like AMPCOLOY® series are versatile materials that find extensive use in a variety of applications, including the production of non-ferrous faucets, fixtures, and water mixers through the low pressure die casting process. Key benefits of using high conductivity copper alloys for gravity die casting molds include:

• High Strength: High conductivity copper alloys are strong and robust materials that can withstand high-stress levels and wear.
• Corrosion Resistance: High conductivity copper alloys are highly resistant to corrosion, rendering them perfect materials for use in harsh environments.
• Excellent Machinability: High conductivity copper alloys are easy to machine and can be finished with high precision and accuracy.
• Superior Thermal Conductivity: High conductivity copper alloys have excellent thermal conductivity, making them ideal for use in applications where heat transfer is crucial.
• Good Weldability: High conductivity copper alloys are easy to weld and can be joined to other materials using various welding techniques.

Our solution for your gravity die casting tooling

As an integrated partner that understands specific application needs, AMPCO METAL produces a full range of high-performance alloys for the gravity die casting tooling industry that ensures repeatability and reliability. 

Our patented MICROCAST® technology gives our metal a refined microstructure which, combined with the high hardness and thermal conductivity of our alloys, improves wear resistance for maximum life and performance.

In particular, AMPCOLOY® 83, AMPCOLOY® 88, AMPCOLOY® 95, AMPCOLOY® 940, and AMPCOLOY® 944 are all higher-grade metals designed for reliable, high productivity, especially in die casting molds used in the production of non-ferrous faucets, fixtures, and water mixers in the low pressure die casting process. Combined with a process that allows for control and molding, these metals can produce a better surface finish with far superior mechanical properties.