Many existing methods of producing copper alloy castings may be broadly subdivided into six separate headings as follows:
- Sand casting is a traditional copper-alloy casting technique. Other casting processes under sand casting include green sand molding, furan resin sand casting, and the CO2 process. The advantages of sand casting are its mature techniques and its ability to produce unique shapes that are not obtainable through other casting processes.
- Shell mold casting is a type of expendable mold casting process. A shell mold is first produced. In this mold-making process, two half-molds are made by covering metal patterns with fine-grained sand and baking the sand-covered metal patterns. The two baked half-shells based on the sand are then combined to form the mold. One advantage of this process is that it requires less manpower and molding skills. The other advantages of shell mold casting include good dimensional accuracy, smooth surface finish, and fewer defects on the casting surface.
- Gravity die casting is also a traditional casting technique. It is often used on non-ferrous metals and alloys, such as aluminum, zinc, and coppers. This process is suitable for some types of copper alloys, such as aluminum bronzes, certain brasses, and tensile brasses. During gravity die casting, molten metal is poured from a crucible into a mold through the aid of the force of gravity. The advantages of gravity die casting are excellent surface finish, high dimensional accuracy, and excellent mechanical properties.
- Chill casting is a semi-continuous casting process. A chill is a piece of metal used to help solidify pre-determined areas within a mold through heat transfer. Therefore, chill casting is based on permanent molds made from heat-resistant steel or cast iron consisting of flake graphite. The metal molds provide excellent thermal conductivity and consequently good outcomes. This casting technique is used for casting pure copper or copper alloys. In addition, chill casting is ideal for casting complex parts requiring high surface quality, high density, and firm structure.
- Centrifugal casting for copper alloys often uses permanent molds or sand molds. The centrifugal force during the casting process leads to denser and more reliable casting results. Initially used for casting bearings, cored bars, gears, and worm wheels, centrifugal casting is commonly used for large castings. This process includes vertical and horizontal centrifugal castings; horizontal centrifugal casting is also used to cast small parts.
- Continuous casting is a relatively new technique for copper alloy casting. This process is used to cast a continuous length of material. The casting length is cut by a saw instead of being determined by the mold. In continuous casting, the force of gravity helps the molten metal move through a vertical tube-shaped mold. The advantages of continuous casting are less material loss, high productivity, consistent material properties, and good quality outcomes.
Stinco provides casting services for various copper alloys. Our casting processes include sand casting, centrifugal casting, gravity casting, and continuous casting. Most of our products are made by sand casting, including mechanized molding (green sand mold process) for small parts and furan resin sand casting for large castings. Meanwhile, Stinco can produce centrifugal casting materials that are defect-free, high-density, high-strength, and durable. Our castings meet with customers' approval in multiple applications. Please check our Applications.