There are mainly two types of sand casting and special casting.
1 Ordinary sand casting, which uses sand as a mold material, also known as sand #casting and sand casting, includes three types of wet sand, dry sand and chemically hardened sand, but not all sands can be used for casting. The advantage is that the cost is lower, because the sand used in the casting mold can be reused; the disadvantage is that the casting mold is time-consuming, and the casting mold itself cannot be reused, and the finished product can only be obtained after being destroyed.
1.1 Sand mold (core) casting methods: wet sand mold, resin self-hardening sand mold, water glass sand mold, dry mold and surface dry mold, solid mold casting, negative pressure molding.
1.2 Sand core manufacturing method: It is selected according to the size, shape, production batch and specific production conditions of the sand core. In production, it can be generally divided into manual core making and machine core making.
2 Special #casting can be divided into special #casting with natural mineral sand as the main molding material according to the modeling material (such as investment casting, mud casting, shell casting, negative pressure casting, solid casting, ceramic casting, etc.) And special#casting with metal as the main #casting material (such as metal mold casting, pressure casting, continuous casting, low pressure #casting, centrifugal casting, etc.).
2.1 Metal mold casting method
The mold is made of metal with a higher melting point than the raw material. It is subdivided into gravity casting method, low pressure casting method and high pressure casting method.
The metal that can be cast is also limited by the melting point of the mold.
2.2 Lost wax casting method
This method may be an outer membrane casting method and a solid casting method.
The object to be cast is first replicated in wax, then immersed in a bath containing ceramic (or silica sol) and allowed to dry, so that the wax replica is covered with a ceramic outer film, and the steps are repeated until the outer film is sufficient to support the casting process (about 1/4″ to 1/8″), then melt the wax in the mold and pull away from the mold. After that, the mold needs to be subjected to high temperature for many times, and the hardness can be increased before it can be used for casting.
This method has good accuracy and can be used for #casting of high melting point metals such as titanium. However, due to the high price of ceramics, and the need for multiple heating and complex production, the cost is quite expensive.