Brief introduction of several common methods of precision casting
Precision casting is a kind of casting method that can cast near-precision castings. Investment casting is not a single method. The main and commonly used methods include investment casting, metal mold casting, pressure casting, centrifugal casting, lost foam casting, etc. The production process of each casting method is different, and each has its own scope of application.
Investment casting: investment casting refers to the casting method of using patterns made of fusible materials, wrapping several layers of refractory coating on the surface of the patterns to make the mold shell, melting the patterns out of the mold shell, so as to obtain the mold without parting surface, and then filling sand and pouring after high temperature roasting. The process is divided into three stages: wax mold manufacturing, shell manufacturing, and baking and pouring.
Metal mold casting: Metal mold precision casting is a method of pouring liquid metal into the metal mold and solidifying under the action of gravity. It can be used repeatedly in occasional cases, so it is called permanent casting.
Pressure casting: pressure casting is a method of rapidly pressing liquid or semi-liquid alloy (filling speed up to 5~50 m/s) into the metal mold under high pressure (specific pressure is about 5~150 MPa) and solidification under pressure to obtain castings.
Centrifugal casting: The liquid alloy is poured into the high-speed rotating mold to fill the mold and crystallize under the centrifugal force. This casting method is called centrifugal casting.
Lost foam casting: Lost foam casting precision cast steel is also called gasified mold casting or full mold casting. It is a method of making casting by using the pattern made of foam plastic, and then the pattern is not taken out, and the pattern evaporates during pouring to obtain the casting.
The characteristics of precision castings produced by different casting processes will also be different, so we should select the appropriate precision casting method according to the product characteristics.