A Complete Beginner's Guide to Vacuum History, Terminology, & Technology Vacuum technology is used to define all physical measurements and processes that are performed below normal atmospheric pressure. For any process to be carried out in vacuum, the permissible pressure can be determined by any of the three parameters namely: the number of molecules per unit volume, the mean free path, or time needed to create a monolayer. The first use of vacuum technology happened about 1900 with the production of electric light bulbs. Vacuum is used in light bulbs to protect the filament from chemical degradation. Other developments that happened with the help of vacuum technology are the blooming of lens surface, blood plasma preparation, and production of metals such as titanium. Industrial uses of vacuum technology are mechanical handling, gas sampling, degassing, filtration, distillation, and impregnation of electric components. Vacuum produces chemical inertness that is highly used in vacuum packing, cold welding, electron beam welding, and vacuum frying. High pressure vacuum removes the blockage of air and thus allow the particle beam to deposit materials without any contamination. This principle is used in physical vapor deposition, dry etching, and chemical vapor deposition. Vacuum technology is also used in research, directly in the experiments or to employ devices that work under vacuum. Important Names in Vacuum Technology - Amadeo Avogadro: Amadeo Avogadro is a physicist who set forth Avogadro’s Law, which states that the equal volume of vapors or gases at same pressure and temperature contains the same number of molecule. In 1811, he published an essay in the Journal of Physics that clearly stated the difference between the atom and the molecule.
- Avogadro’s number: The Avogadro’s number is defined as the number of molecules in one kilogram mole of the substance and the value of this number is 6.023 × 10²? in mks units. The name Avogadro’s number is changed to Avogadro Constant when mole is introduced as the separate unit in the SI units.
- Ludwig Eduard Boltzmann: Ludwig Eduard Boltzmann is a physicist who explained and predicted the effect of properties of atom over the visible properties of matter. He founded and developed a branch of theoretical physics called statistical mechanics. Boltzmann introduced the Boltzmann Constant K, which became the fundamental constant of physics.
- Robert Boyle: Robert Boyle is a natural philosopher and a chemist who is well-known for his experiment on espousal of molecular view of matter and properties of gases. Boyle set forth Boyle’s Law which states that at fixed temperature, the volume and pressure of the gas are inversely proportional.
- Jacques-Alexandre Charles: Jacques-Alexandre Charles is a physicist, mathematician, and inventor and he is famous for building the first hydrogen balloons. He set forth Charles Law, which states that at fixed pressure, the volume and pressure of the gas are inversely proportional.
- John Dalton: John Dalton is worshipped as one of the fathers of modern science. He is a famous physicist and chemist who formulated the atomic theory. He formulated the Dalton’s Law of partial pressure, which states that the total pressure of the gas is equal to the partial pressure of each component in the gas.
- Evangelista Torricelli: Evangelista Torricelli is a famous mathematician and physicist and he is well-known for inventing barometer. He is the first person to make the sustained vacuum and he wrote “Concerning Movement”, a treatise on mechanics.
- Joseph Fourier: Joseph Fourier is a brilliant mathematician who formulated the partial differential equations that explain steady state propagation of heat in solid bodies. He used infinite trigonometric equations to solve the equations, which is now popularly known as Fourier Series.
- Gustave de Coriolis: Gustave de Coriolis is famous for his finding of the Coriolis force with respect to centrifugal motion. He also developed the relationship between the work and kinetic energy in solid bodies. In 1945, he published an article on how energy is produced in machines with rotating parts.
- Hendrik A. Lorentz: Hendrik A. Lorentz is famous for his hypothesis Fitzgerald-Lorentz Contraction. He improved Maxwell’s electronic theory and got Nobel Prize for his mathematical theory of the electron. In his doctoral thesis, Lorentz made changes and improved Maxwell’s electromagnetic theory.
- Blaise Pascal: Blaise Pascal is famous for inventing first digital calculator. He also invented syringe and hydraulic press. He developed Pascal’s Law of pressure, which states that the pressure created in the confined fluid is equally transmitted in all directions.
- Christaan Huygens: Christaan Huygens is a technical physicist and first to patent pendulum clock. He made the first practical vacuum pumps and developed the law of centrifugal force. He is well-known for his wave theory of light and he is the first person to propose that Saturn is surrounded by a ring.
- Joseph-Louis-Gay-Lussac: Joseph-Louis-Gay-Lussac derived the Law of Combining Volumes and famous for his theories on the interactions of gases. He also developed the tall absorption towers for the production of sulphuric acid, which is commonly referred as Gay-Lussac Towers. His research on iodine is considered by most researchers as the best example of chemical research.
- Otto von Guericke: Otto von Guericke is a famous natural philosopher, engineer, and physicist who made the first air pump. He also built a device to develop an electric spark. He used barometer to predict weather conditions and he made the first electrostatic generator.
Vacuum Technology Equipment - Rotary Pump: A rotary pump consists of vanes that are mounted on a rotor, which rotates inside the cavity. The common uses of this pump are in ultraviolet spectrometers, food packaging, and in high-speed centrifuges.
- Mechanical Booster: Mechanical booster are diaphragm pumps that contain a pump chamber whose intensity is increased or decreased by the flexible diaphragm. The typical use of mechanical booster is to pump vacuum-melting furnaces.
- Molecular Pump: Molecular pumps are also known as momentum transfer pumps that uses high-speed rotating blades or high-speed dense fluid to blow gas molecules outside the chamber. This type of pumps is used in semiconductor processing.
- Diffusion Pump: A diffusion pump uses high-speed vapor to flow gas molecule to the bottom of the pump and push it out through the exhaust.
- Sputter Ion Pump: An ion pump or sputter ion pump ionizes gases and uses strong electric potential to accelerate gases into a solid electrode. This kind of pumps is used typically in ultra high vacuum systems.
- Mass Spectrometer: The mass spectrometer is a device that measures the relative density and masses of atoms and molecules.
- Ground Penetrating Radar: The ground penetrating radar uses radar pulses to produce the cross-sectional and two-dimensional image of the subsurface features.
Vacuum Technology Literature
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