In order to meet the needs of various performance of vacuum pump, there will be many requirements in the selection of vacuum pump shell material, especially in some harsh working medium environment. What are the specific shell materials and what are the requirements?

There are many kinds of vacuum pump materials, such as metal alloy, ceramic, rubber plastic, glass quartz, carbon fiber and so on. And the vacuum pump shell material is mainly two categories: metal and glass.

As the material of vacuum shell, metal mainly includes iron, copper and aluminum based metals and various alloys, such as low carbon steel, stainless steel, oxygen free copper, red copper, aluminum and steel or iron materials coated with aluminum, copper and nickel. They have good mechanical strength and machinability. Various metal materials have different performance and outgassing rate according to different vacuum application characteristics. The physical and mechanical properties of various metal alloys can be inquired.

Glass is mainly used in some glass vacuum system (such as glass diffusion pump, valve), observation window and some regulatory shell, high-voltage electrode insulator, etc. it has the advantages of transparency, low price, easy processing and insulation, but the disadvantage is low strength and fragile. According to the different softening temperature and expansion coefficient, there are soft glass, hard glass and quartz glass with different properties.

Whether it is metal or glass, the shell material of vacuum pump needs to have: certain mechanical strength and stiffness, which can ensure that it can withstand atmospheric pressure at normal temperature and baking temperature without deformation; good air tightness, without defects such as porous structure, cracks and other leakage; low gas outlet rate and penetration rate; low saturated vapor pressure under working temperature and baking temperature It has good chemical stability, is not easy to oxidize and corrode, and will not react with the working medium in the system; it has good temperature stability and can maintain its vacuum performance and mechanical property within a certain temperature range; it is easy to process, has good welding performance and good economy.