Common Methods of Casting Copper Parts
Cast copper parts are usually filled into the mold cavity by low-speed or high-speed casting with liquid metal. The mold has a movable cavity surface. During cooling of liquid metal, pressure forging can not only eliminate the shrinkage defects of the blank, but also make the internal structure of the blank reach the broken grains in the forged state. Below common methods are adopted for casting copper parts:
1. For copper alloy casting, normally metal mold casting is applied to accelerate the solidification of the alloy, which plays an important role in improving the quality of castings and reducing casting defects. Metal mold casting can refine the grains, reduce pores, and improve the mechanical properties and air tightness of the alloy. For alloys with high lead content such as lead bronze, the use of metal mold casting can prevent the component segregation.Due to the fact of many cylindrical parts in copper alloy castings, centrifugal casting method is more used.
2. Centrifugal casting is the technology and method of injecting liquid metal into the high-speed rotating mold to make the liquid metal centrifugal to fill the mold and form the casting. With centrifugal movement, the liquid metal can fill the mold well in the radial direction and form the free surface of the casting; Cylindrical inner holes can be obtained without cores; It is conducive to the elimination of gases and foreign substance in liquid metals; Affect the crystallization process of metal, thus the mechanical and physical properties of castings improved.
In terms of casting methods, in addition to sand casting, low-pressure casting can also be used for large cast copper handicrafts to improve the density of the alloy and reduce the foreign impurity produced in the casting process.