A. Means and Purposes

Read text A. Pay attention to the words in bold type.

Translate the sentences. Pay attention to the words in italics.

Copper impregnation procedure vital

Composite gap predict vac. Engineering

Ceramics filter polymer vacuum-deposited

Capture fabrication perspective tribological

Bronze exciting pick up titanium dioxide

Brass environment nanotube storage

Booster ESI nanotechnology spread

Blower efficiency modeling spin

Bio-structure edge mimic sensor

Attenuate device microchip repair

Appearance demand layer replacement

Analyte daunt innovative repair

Accessory damage implantation productivity

Words to be remembered.

Unit VII. Vacuum Engineering and Its Prospects

Kinetic Devices (General View).

Make notes under the following headings. Then use your notes to talk about it.

Follow-up Activity

2. Compressors’ Operation and Designs.

3. Gas Compressors’ Application.

4. Compressors’ Branches and Purposes.

5. Refrigerator Compressor.

6. Amadeo Avogadro and his Accomplishments.

Before you start: Think it over. Agree-Disagree

“Any sufficiently advanced technology is indistinguishable from magic”. Arthur C. Clarke

Reading, Vocabulary & Creative Practice

1.Car accessories include the roof rack, rubber mat, mirrors.

2.It is clear that a booster pipeline is needed in this case.

3.The data is captured by means of an optical scanner.

4.Smoking can damage your health.

5.The missile has the device which enables it to find its target.

6.It would improve our efficiency if we used more up-to-date methods.

7.The whole story was a complete fabrication.

8.If our industries don’t use innovative methods we will never succeed.

9.These seeds must be covered with a layer of earth.

10.New production methods have led to high productivity.

11.The pump is under repair.

12. Sensor is an apparatus used for discovering of a particular quality.

13.The steam spins a turbine to produce electricity.

14.Your support is vital for the success of my plan.

Vacuum engineering deals with technological processes and equipment that use vacuum to achieve better results than those run under atmospheric pressure. Either vacuum coatings or films, vacuum impregnation, vacuum deposition, electro-spray ionization, plasma spraying techniques, metal properties and many other things are of practical use and large interest for vacuum engineers and scientists, who take an active part in innovative developments. The purpose of vacuum engineering is to provide innovative solutions for helping to improve productivity and efficiency in manufacturing processes. For example, when handling metal pieces in automotive stamping applications, it is particularly vital to have flexible tooling because changes in size occur each time the vehicle model or car part changes. In the case of sheet metal stamping applications, vacuum is used to pick up the metal sheet and transport it to the next destination.

Vacuum deposition is a process used to create a thin layer of a substance (a coating) on a solid object (the substrate). The substrate is placed into a vacuum chamber and a small amount of the coating material is vaporized into the chamber. The molecules or atoms of vapor condense onto the substrate, forming (ideally) a uniform coating of controllable thickness. Many such layers can be built up, for example (in optics) to form an interference filter or other multiplayer optic, or (in microelectronics) to form different layers within a complex microchip.

Vacuum deposition is very commonly used in the fabrication of optics. Everyday objects that are created by vacuum deposition include mirrors, which are most frequently made of a glass substrate with aluminum or silver vacuum-deposited onto it; sunglasses, which often use vacuum-deposited coatings to attenuate light; and electronic microchips, which are fabricated using a combination of vacuum deposition and photography.

Common vacuum deposition techniques include sputtering, in which the vapor is created by directing an electron beam at a target made of the material to be deposited; and ion implantation, in which ions of the coating material are accelerated directly to land on the surface of the substrate.

Electro-spray ionization (ESI) is a technique used in mass spectrometry to produce ions. It is especially useful in producing ions from macromolecules because it overcomes the propensity of these molecules to fragment when ionized. In nanotechnology the electro-spray method may be employed to deposit single particles on surfaces.

Plasma spraying is a technique for producing coatings using a plasma jet. Deposits having thickness from micrometers to several millimeters can be produced from a variety of materials – metals, ceramics, polymers and composites. This technique is mostly used to produce coatings on structural materials. Such coatings provide protection against high temperatures, corrosion, erosion, wear; they can also change the appearance, electrical or tribological properties of the surface, replace worn material, etc. It can also be used for powder processing, modification of chemistry, etc. In that case, the substrate for deposition is absent and the particles solidify during flight or in a controlled environment (e.g. water). Vacuum coating processes consist of a source of vapor (atomic or molecular) of the material to be deposited. Such metals as brass, copper, bronze are popular in decorative coatings.

Spin coating is a special procedure used to apply uniform thin films to flat substrates. In short, an excess amount of the solvent is placed on the substrate, which is then rotated at high speed in order to spread the fluid by centrifugal force. Rotation is continued while the fluid spins off the edges of the substrate, until the desired thickness of the film is achieved. The applied solvent is usually volatile, and simultaneously evaporates. So, the higher the angular speed of spinning, the thinner the film is. The thickness of the film also depends on the concentration of the solution and the solvent. A device used for spin coating is called a spin coater, which is very popular in semiconductor industry. Spin coating can be used to create very thin films.

Vacuum impregnation sealing is not an external coating process, rather it is a process that internally seals parts using a vacuum pressure chamber, which impregnates liquid resin into minute pores in the part's surface. The process was previously used to seal porous parts, such as transmission housings and power steering pumps, to make them impermeable to liquids and gases, but it is now enjoying a renaissance of use by electronic OEMs who seek a competitive edge in terms of quality.

Since vacuum engineering and equipment are in great demand, there are many firms around the world, which supply a wide range of vacuum equipment, including replacement parts and accessories to various pumps, compressors, boosters as well as blowers, etc.

Comprehension Check – 1

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