What are the vacuum pumps for experimental vacuum sintering muffle furnaces?

The commonly used vacuum pumps for experimental vacuum sintering muffle furnaces are as follows:

Rotary vane vacuum pump
Working principle: By rotating the rotary vane in the pump chamber, a periodic volume change is formed, thereby achieving the purpose of suction and exhaust.
Features: Simple structure, small size, low working noise, able to work in a wide pressure range, fast start-up, can achieve a high ultimate vacuum degree, generally up to 10 ⁻ -10 ⁻ ³ Pa.
Application scenario: Suitable for experimental vacuum sintering muffle furnaces that do not require particularly high vacuum levels, commonly used for pre vacuuming or as a front-end pump in conjunction with other high vacuum pumps.
Reciprocating vacuum pump
Working principle: By relying on the reciprocating motion of the piston in the cylinder, the pump chamber volume periodically changes to extract air.
Features: Large pumping capacity, able to operate at lower inlet pressures, insensitive to dust and water vapor in the pumped gas, reliable operation, and simple maintenance. But the ultimate vacuum degree is relatively low, generally around 10-100Pa.
Application scenario: Suitable for situations that require a high pumping rate and do not have strict requirements for vacuum degree, such as experiments that require high sintering speed and allow the presence of certain impurity gases.
ROOTS VACUUM PUMP
Working principle: Two 8-shaped rotors mesh with each other and rotate. During the rotation process, gas is carried by the rotors from the inlet to the outlet and discharged.
Features: It has a high pumping rate and a wide pumping range, can work at lower inlet pressures, and can achieve a high vacuum degree, generally reaching 10 ⁻³ -10 ⁻⁴ Pa. However, it cannot be used alone and needs to be combined with a front-end pump.
Application scenario: It is commonly used in experimental vacuum sintering muffle furnaces that require fast pumping and high vacuum requirements. When combined with front-end pumps such as rotary vane vacuum pumps or reciprocating vacuum pumps, it can greatly improve pumping efficiency and vacuum degree.
Diffusion pump
Working principle: Utilizing high-speed oil vapor or mercury vapor flow to bring gas molecules to the outlet of the pump, thereby achieving pumping.
Features: It can achieve a high vacuum degree, with a maximum vacuum degree of 10 ⁻⁵ -10 ⁻⁷ Pa or even higher. It has a high pumping rate and good ability to remove condensable gases such as water vapor. But it requires heating and cooling devices, longer start-up time, and higher requirements for the working environment.
Application scenario: Mainly used for experimental vacuum sintering muffle furnaces with extremely high vacuum requirements, such as experiments in high-precision material research, semiconductor manufacturing, and other fields, to obtain ultra-high vacuum environments.
molecular pump
Working principle: By rotating the rotor at high speed, gas molecules gain directional velocity, thereby transporting them from the inlet to the outlet.
Features: It can achieve ultra-high vacuum degree, with a maximum vacuum degree of 10 ⁻⁸ -10 ⁻¹⁰ Pa, fast pumping speed, good pumping effect on inert and light gases, clean and pollution-free, stable and reliable operation. But the price is relatively high, and strict requirements are placed on the installation and usage environment.
Application scenario: Commonly used in experimental vacuum sintering muffle furnaces that require extremely high vacuum and cleanliness, such as aerospace material research, high-end electronic component manufacturing, etc., to meet their demand for ultra-high vacuum environments.