The scope of application of vacuum technology

With the development of vacuum science, vacuum technology applications are expanding to all aspects of industry and scientific research. Vacuum applications refer to the use of the physical environment of a rarefied gas to accomplish certain specific tasks. Some use this environment to make products or devices, such as light bulbs, electron tubes, and accelerators. These products maintain a vacuum throughout; others treat a vacuum only as a step in production, and the final product is processed in atmospheric environments such as vacuum coating, vacuum drying, and vacuum impregnation.

Vacuum technology has a wide range of applications, mainly divided into low vacuum, medium vacuum, high vacuum, and ultra high vacuum applications.

Low vacuum applications are the use of the pressure differential obtained by low (rough) vacuum to grip, lift and transport materials, as well as vacuum and filter dust, such as vacuum cleaners, and vacuum suction cups.

Medium vacuum is generally used for removing occluded or dissolved gas or moisture in materials, manufacturing light bulbs, vacuum metallurgy, and thermal insulation. Such as the production of condensed milk by vacuum concentration, the moisture in the milk can be evaporated without heating.

Vacuum metallurgy can protect active metals from oxidation during melting, casting, and sintering, such as vacuum melting of active refractory metals tungsten, molybdenum, tantalum, niobium, titanium, and zirconium; vacuum steelmaking can avoid some of the added The burning of a small number of elements at high temperatures and the infiltration of harmful gas impurities can improve the quality of steel.

High vacuum can be used for thermal insulation, electrical insulation, and avoiding the collision of molecular electrons and ions. The free path of molecules in a high vacuum is larger than the linear dimension of the container, so high vacuum can be used in devices such as electron tubes, photocells, cathode ray tubes, X-ray, accelerators, mass spectrometers, and electron microscopes to avoid molecules, electrons, and ions. collision. This feature can also be applied to vacuum coatings for optical, electrical, or plated decorative applications.

Energy transfer in outer space is similar to that in an ultra-high vacuum, so the ultra-high vacuum can be used as a space simulation. Under ultra-high vacuum conditions, the formation of monolayers takes a long time (measured in hours), which allows a sufficiently long period of time to study surface properties such as friction, adhesion, launch, etc.