The main functional purpose of a vacuum installation is to create and maintain a technical vacuum, which is achieved by pumping out the mixture from the system. Vacuum units are widely used in the metallurgical, textile, chemical, automotive, food and pharmaceutical industries. The main parts of the installation include a pump, a panel with filters, and a camera control unit.
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Application of vacuum installations
Vacuum units can be used for laboratory research. Included in microscopes, chromatographs, evaporators and filtration systems. For these purposes, a unit that will not occupy a large area may be suitable. The performance of such units does not come first. Most often this is a forevacuum or turbomolecular pump. When working with aggressive gases the best option– membrane pump.
Vacuum units play an important role in testing equipment. They provide the necessary rate of climb aircraft. In order for the takeoff or landing process to proceed successfully, it is necessary to ensure a fast pumping speed. 
Dry pumps are used for semiconductor and deposition vacuum installations, for the deposition of materials. Ideal for creating ultra-high vacuum. These include turbomolecular and cryogenic pumps.
The metallurgical industry actively uses pumps that have sufficient throughput. They must be wear-resistant, since the system contains dust and dirt. Claw and screw pumps performing fore-vacuum pumping. It is possible to use diffusion pumps.
Vacuum unit 976A is a laboratory type. It is designed to determine the water saturation of asphalt concrete in laboratory conditions. The working volume of the chamber is 2 liters. The vacuum installation is capable of creating a final vacuum with a value of 1x10-2.
Elements of vacuum installations
Vacuum installations create and maintain a working vacuum in a certain sealed volume. As a rule, elements that have the same purpose are used for this purpose. various types installations. They include a control unit with a control rack, a vacuum unit, a sub-cap device, cooling systems and a vacuum system and a cap lifting drive. The vacuum system consists of any type of pump, vacuum unit, pipelines, vacuum gauge and electromagnetic leak.
Vacuum units Busch
Busch vacuum units are, first of all, high-quality vacuum pumps. The company produces such units as the rotary vane model of the R5 vacuum pump. She's different high quality and productivity. The maximum pressure of the unit ranges from 0.1 to 20 hPa. The pumping speed of the medium reaches 1800 m3/h. Secondly, these are cam pumps and compressors. One of these is the Mink model. Widely used in industry. Especially where it is necessary to maintain a constant vacuum level. The maximum pressure ranges from 20 to 250 hPa. Pumping speed can reach 1150 m3/h.
Vacuum installations Bulat
One example of installations for applying thin-film coatings is the Bulat model. It applies film using a vacuum-plasma method. Can produce coating through other electrically conductive materials. These are molybdenum, zirconium, nitride and carbonitride. Initially, the model was developed for coating metal dentures. The installation includes a pumping station, a fore-vacuum tool and associated electrical equipment. 
Other manufacturers of vacuum systems
Agilent Technologies is one of the largest manufacturers of vacuum equipment. The company produces vacuum pumps, leak detectors, vacuum gauges, vacuum oils and other components of systems.
Air Dimensions Inc. specializes in the mass production of high-quality diaphragm-type pumps, which carry out sampling of corrosive gases, as well as dry diaphragm compressors.
Edwards produces laboratory and industrial vacuum equipment. Among them are vacuum pumps, vacuum gauges and more. auxiliary equipment. It is famous for producing a wide range of pumps of various types.
Vacuum spraying plants
Using a vacuum deposition unit (VSP), various parts are coated with coatings that perform conductive, insulating, wear-resistant, barrier and other functions. This method is the most common among other microelectronics processes in which metallization is used. Thanks to such installations, it is possible to obtain antireflective, filtering and reflective coatings.
Aluminum, tungsten, titanium, iron, nickel, chromium, etc. can be used as coating materials. If necessary, acetylene, nitrogen and oxygen can be added to the medium. Activation of a chemical reaction during heating, ionization and dissociation of gas. After the coating procedure, no additional processing is required.
The UVN-71 P-3 installation is capable of testing technological spraying. It is involved in the serial production of various film circuits. With its help, thin films are produced under high vacuum conditions. The method used is resistive evaporation of metals.
The UV-24 vacuum unit performs laboratory tests of asphalt concrete. Helps determine its quality. Distinctive feature of this unit - the presence of two pumped tanks, which are connected to each other.
Magnetron sputtering
In magnetron sputtering, a thin film is deposited using cathode sputtering. Devices using this method are called magnetron sputterers. This installation can produce spraying of many metals and alloys. When used in various working environments with oxygen, nitrogen, carbon dioxide, etc. films with different compositions are obtained.
Ion sputtering
The principle of operation of an ion installation in a vacuum is the bombardment of solids with ions. When the substrate is placed in a vacuum, atoms hit it and a film is formed.
Other spraying methods
Vacuum spraying can be carried out using periodic and continuous equipment. Installations with periodic action are used for a certain number of processed products. In mass or batch production, continuous plants are used. There are single- and multi-chamber types of spraying equipment. In multi-chamber installations, the spraying modules are arranged in series. All chambers are sprayed with a certain material. Between the modules there are airlock chambers and a transport conveyor device. They carry out operations to create a vacuum, evaporate the film material, and transport separately.
Vacuum units
Vacuum water ring pumping unit type VVN 12 produces suction of air, non-aggressive gases and other mixtures that cannot be cleared of moisture and dust. The gas entering the installation does not require purification.
The AVZ 180 spool valve vacuum unit is universal, has a good maximum residual pressure, is light in weight, and is fast and compact.
Technical characteristics of the AVZ 180 vacuum spool valve unit.
The AVR 50 vacuum unit is capable of pumping out air, non-aggressive gases, vapors and vapor-gas mixtures from vacuum spaces. It is not intended for pumping the above compounds from one container to another. It consists of two pumps: NVD-200 and 2NVR-5DM. 
The ZENKO PLASM company, in collaboration with FHR Anlagenbau GmbH (Germany), offers vacuum deposition systems for microelectronics, photovoltaics, sensors, optics, MEMS, organic displays (OLED), and for the production of architectural glass. The FHR company is distinguished by the highest German build quality, its own fleet of equipment for demonstration processes, the ability to manufacture almost any system to order and more than 20 years of experience in the production of high-tech equipment. At the same time, FHR is part of the Centrotherm photovoltaics AG holding - one of the world leaders in the production of equipment for photovoltaics, microelectronics, and semiconductor production. ZENKO PLASMA provides consulting, supply, commissioning, warranty and post-warranty service.
Vacuum spraying systems are offered in the following series:
Roll-to-Roll- industrial systems for magnetron or thermal sputtering of metal, oxide and nitride layers on polymer and metal films (on the roll-to-roll principle) with a width of up to 2400 mm (2.4 m). These systems are used in processing roll materials based on thin metal and polymer films, in Food Industry, in the production of flexible (organic) electronics, flexible solar cells (thin-film technologies CIGS, CdTe, a-Si), for the deposition of highly reflective optical coatings, barrier, conductive, insulating layers. The following technological processes are supported: magnetron sputtering (DC, MF, RF modes), surface cleaning with an ion beam, dry etching, thermal spraying, thermal annealing, plasma chemical deposition (PECVD). Depending on the process, a design with a vacuum loading gate is possible.
Line– industrial vacuum deposition systems with horizontal or vertical processing of glass or metal substrates up to 2.2 m wide and up to 4 m long. Mainly used for deposition of transparent conductive oxides (TCO) in the production of thin-film solar cells; in the production of architectural glass to improve heat transfer coefficient and light transmittance; in the production of displays (including OLED), in the field of applying protective coatings. The processing line ensures the highest productivity and quality of sprayed films. Individual configurations are possible depending on substrate dimensions, productivity and deposition process parameters.
Star– this series is a cluster-type system with single processing for small-scale production and R&D in the field of microelectronics, optics, MEMS, sensors. Allows you to work with both single loading of plates with a diameter of up to 300 mm, and with cassettes. The central robot ensures the movement of the substrate between the technological modules of the system. Can be equipped with a wafer loading gateway, technological modules: etching (PE, RIE), thermal evaporation, electron beam evaporation, thermal annealing (RTP/FLA), magnetron sputtering, plasma chemical deposition (PECVD, CVD), atomic layer deposition (ALD) . Systems of this series are relevant when it is necessary to have several technological processes within one installation. Can be installed through a wall in clean rooms.
Boxx– deposition systems of this series provide group processing of substrates in the production of small batches of optical systems, MEMS and sensors. Systems can be equipped with a vacuum loading gateway. Loading of substrates is carried out manually onto a rotating drum inside the working chamber. As the drum rotates, the substrates go through different magnetron sputtering sections (DC, RF), allowing multiple materials to be sputtered in one process. The plasma surface cleaning section is installed as needed. Optionally, it is possible to install up to several such drums, use sluice loading, and also provide heating of the substrates during the deposition process. Can be installed through a wall in clean rooms.
Micro– spraying installations of this series are mainly intended for research, development and small-scale production. The units are designed for single processing of substrates with a diameter of up to 200 mm, including square and rectangular ones. The installations allow the deposition of both metal and dielectric layers. Magnetron sputtering and thermal evaporation systems are available. The systems are distinguished by their compactness, flexible configuration, ease of installation, use and maintenance.
We offer the opportunity to manufacture targets for magnetron sputtering installations. Modern technologies production facilities allow us to produce both planar and cylindrical targets, including non-standard ones according to drawings. The following types of materials are available: metallic, alloys (Al, Cr, Ti, Ni, In), borides, carbides, nitrides, oxides, silicides, sulfides, tellurides. Tell us your requirements and we will provide a suitable solution.
THEORETICAL INFORMATION
The rapid development of the production of microelectronic devices (MEDs) in the last decade has led to the creation of working equipment that would have the least possible impact on the process of forming thin films and would allow their parameters to be controlled. As a result, there is currently big choice vacuum installations, components, as well as materials and installation methods that allow solving complex technological problems in the manufacture of MEPs.
The process of obtaining thin films takes place in the vacuum environment of the under-cap device of the vacuum installation. To reduce the pressure in the subcap device, two principles can be used. In the first, the gas is physically removed from the vacuum chamber and released outside. An example of this method of action is mechanical and steam-jet, steam-oil pumps. Another method of pumping is based on the condensation or trapping of gas molecules on some part of the surface of the vacuum chamber without removing the gas to the outside. Cryogenic, getter and gettero-ion pumps are designed on this principle.
A quantitative measure of the gas transfer or absorption capacity of a pump is its performance (Q). Productivity depends on the pressure in the pumped device and is defined as the amount of gas that flows through the suction pipe of a working pump per unit time at t = 20 0 C:
Q = Fp · P,
where Fp – pumping speed, l/s; P – pressure of pumped gases, mm Hg. Art.
Another parameter characterizing the operation of the pump is the pumping speed Fp, which is defined as the ratio of the pump performance to the partial pressure of a given gas near the pump inlet:
Fp = Q/P
Most vacuum pumps have an almost constant pumping speed over a range of several orders of gas pressure. Above and below this area it drops sharply, so pumping with this type of vacuum pump becomes ineffective.
When choosing a pump for a vacuum installation, you must remember that the pumps themselves, under certain conditions, are sources of residual gases in the vacuum chamber. Different types pumps vary greatly in both the quantity and nature of the gases released. Traces of vapors of organic compounds caused by the working fluids used in pumps are especially harmful.
The main parameters of the pump also include the maximum pressure Pg - this is the minimum pressure that can be obtained using a vacuum pump if the pump itself does not emit gases.
For rotary pumps, Pg depends on the “disadvantage volume” of the pump (that is, that part of the compression chamber from which the gas coming from the object being pumped cannot be displaced) and the vapor pressure of the substances, such as oil, used for sealing. For steam jet pumps, Pg depends on the speed of steam molecules in the nozzle, the speed of gas molecules in the pumped volume and the molecular weight of the gas.
The permissible external (inlet) pressure is the maximum permissible pressure gas at the pump outlet, that is, the pressure at which the pumping speed still remains equal to the maximum value. For fore-vacuum pumps that compress gas to atmospheric pressure, the permissible outlet pressure is equal to atmospheric pressure; for high-vacuum pumps, the permissible outlet pressure is equal to the fore-vacuum pressure.
The process of pumping out a sub-cap device with a volume V and an initial pressure Pо, performed by any pump with a pumping speed Fp and a maximum pressure Pg can be described using a differential equation derived on the basis of the Boyle–Mariotte law. The pressure drop over time is described by the following equation:
DP/dt = Fp/V(P - Pg) (1)
The solution of this differential equation will give a characteristic of the change in pressure P in the pumped-out vessel with time t.
In the case of an “ideal” pump Fp = Fp max = const – the pump characteristic P is a straight line. Speed of pumping Fp all technical pumps unlike “ideal” ones, it depends on pressure , and therefore, the time characteristics of pressure changes are usually obtained not by calculation, that is, by integrating equation 1, but are determined from experiment.
VACUUM SPRAYING INSTALLATION DEVICE
The vacuum installation is designed to create and maintain a vacuum in the working volume (under-cap device). The installation consists of a vacuum unit and a control stand. Structurally, the vacuum unit (Fig. 1.1) is a housing 1, on which an under-cap device 2 is installed. A vacuum system, a cooling system, gas system and a hydraulic drive for lifting the hood. In the under-cap device, the operating gas pressure is set from 1·10 -3 to 5·10 -4 mm Hg. Art. and the materials of the sputtered target are deposited on the substrate using a sputtering device.
The vacuum system of the installation (Fig. 1.2) consists of a mechanical pump NVR-5D and a vacuum unit VA-2-3R-N, a valve box, an electromagnetic leak, pipelines and sensors for measuring pressure.
Fig.1.1. Appearance installations: 1 – body; 2 – cap; 3 – system
vacuum; 4 – cooling system; 5 – mixing mechanism;
6 – spray device; 7 – valve box; 8 – vacuum gauge
The vacuum system pipelines connect it to the mechanical pump, the under-cap device and the outlet pipe of the steam-oil pump. The leak valve is designed to depressurize the working volume.
The pumping means of the vacuum system of the installation are controlled by the vacuum system control unit.
To start the mechanical pump, you must turn on the corresponding toggle switch on the control panel. In this case, the magnetic starter is triggered, which with one normally open contact becomes self-locking, and with the other three contacts turns on the electric motor driving the electromechanical pump in the vacuum unit.
Fig.1.2. Vacuum installation system: 1 – mechanical pump NVR-5D;
2 – lower handle of the valve box; 3 – electromagnetic leak;
4 – upper handle of the valve box; 5 – valve box;
6 – thermocouple; 7 – pressure sensor; 8 – leak valve;
9 – shutter; 10 – vacuum unit type VA-2-3RM; 11 – pipelines
To turn on the mechanical pump, you must turn on the corresponding toggle switch on the control panel. In this case, a magnetic starter is activated, which
one normally open contact switches to self-locking, and the other three contacts turn on the electric motor driving the electromechanical pump in the vacuum unit
Turning on the heater of the EN-1 steam oil pump is possible only after turning on the mechanical pump, since the magnetic starter is powered through the normally open contact of the magnetic starter, and the signal lamp on the control panel lights up.
With the help of valve box 2, all switching of the vacuum system necessary for the operation of the installation is provided. The valve box control is located on the front pillar of the installation (Fig. 1.1). When the upper handle of the mechanical pump is pulled out, the working volume of the under-cap device is pumped out; when the lower handle is pulled out, the cavity of the steam-oil pump is pumped out.
The electromagnetic leak is located on valve box 5 and is designed to let atmospheric air into the pipeline of a mechanical pump.
The electromagnetic leak is turned on by the “lead” switch located in the vacuum system control unit. The leak only operates if the mechanical pump is switched off. When the lower handle of the valve box is extended, the same leak lets atmospheric air into the cavity of the steam-oil pump. Structurally, the leak is a solenoid, the end part of which is made in the form of a sealing valve. The vent has a porous glass filter that traps dust particles from the air.
Vacuum control is carried out by a VIT-2 vacuum gauge from sensors connected to it with the “Sensor selection” switch.
When the “Sensor Selection” switch is set to position “1”, the vacuum gauge measures the low vacuum in the foreline line. When set to position “2”, the high vacuum in the under-cap device is measured using an ionization pressure sensor; when switched to position “0”, both sensors are turned off.
Mechanical vacuum pump. A vane-rotor type pump with an oil seal is designed for pumping out air, chemically inactive gases and vapor-gas mixtures that do not affect structural materials and working fluid. Such pumps can normally pump out condensed vapors and vapor-gas mixtures of acceptable concentrations.
The process of pumping gases in rotary vane pumps is based on mechanical suction of gas due to periodic increase in the working chamber.
The principle of operation of such a pump is illustrated in Figure 1.3 and proceeds as follows.
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Fig.1.3. Rotary vane pump: 1 – cylinder; 2 – rotor; 3 – shoulder blades;
4 – spring; 5 – valve; A and B – cavities
In cylinder 1, an eccentrically mounted rotor 2 rotates in the direction indicated by the arrow. Blades 3 are placed in the slot of the rotor, which are pressed against the inner surface of the cylinder by a spring 4. When the rotor rotates, the blades slide along the inner surface of the cylinder, the cavity formed by the cylinder, rotor and blades is divided into cavity A and cavity B.
As the rotor rotates, the volume of cavity A periodically increases and gas enters it from the pumped out system; the volume of cavity B periodically decreases and compression occurs in it. The compressed gas is released through valve 5. The seal between the suction cavities A and compression B is carried out using an oil film. This is how a single-stage pump works. In a two-stage design, the output of the first stage is connected to the input of the second stage and the gas is released into the atmosphere through the valve.
All rotary vane pumps have a similar design, but differ in size, which determines the pumping speed of the pumps. The design of a single-stage rotary vane pump is shown in Figure 1.4.
When connecting the pump to a vacuum system, the pipeline must have a short length and a large diameter, not less than the diameter of the pump inlet. Failure to comply with these conditions leads to a decrease in the pumping speed of the pump.
The mechanical rotary vane pump VN-05-2 used in the installation has the following main performance characteristics:
Pumping speed 0.5 l/s
Residual pressure 5·10 -3 mm Hg. Art.
High vacuum steam oil pump. High-vacuum steam-oil pump N-05 is designed for pumping air, non-aggressive gases, vapors
and steam-gas mixtures.
The pump must only operate in conjunction with an auxiliary pre-discharge pump. The location of the steam oil pump in a high vacuum system is shown in Figure 1.5.
Widely used three-stage steam-oil pumps consist of the following main components: housing, steam line, electric heater, oil slinger and hydraulic relay. The pump design is shown in Figure 1.5.
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Pump housing 1 is a steel cylinder with a bottom welded to it, an inlet flange 2, an outlet pipe with a flange 3. To install the ejector parts, there is a sealed flange 4 on the outlet pipe.
Fig.1.5. General form pump: 1 – electric heater; 2 – steam line; 3 – body; 4 – oil deflector; 5 – nozzle; 6 – butt pad;
7 – nozzle; 8 – butt pad; 9 – ejector nozzle
The main structural part of the pump is a steam line in which the oil circulates in such a way that oil vapors from the boiler located in the lower part of the housing through steam-conducting channels enter the upper, lower and ejector nozzles, exiting, from where they condense on the cold walls of the pump housing and the outlet pipe . Flowing into the boiler, the oil first enters the section of the boiler connected to the last (exhaust) nozzle and only lastly, passing through the labyrinth, it enters the section connected to the most critical internal steam line that supplies steam to the high-vacuum nozzle. Thanks to this, the high-vacuum nozzle closest to the pumped object operates only on oil that has the lowest saturated vapor pressure, and the nozzle closest to the pre-discharge pump operates on the lightest fractions.
The pump's steam line is three-stage. The first two stages are umbrella type, the third stage is ejector. Oil vapors from the boiler enter the nozzles of the three stages of the pump through steam lines and, flowing out of them, form jets. The pumped gas diffuses into the steam jets and is transferred by them to the pre-discharge area. The steam, having reached the cooled wall of the pump, condenses and flows back into the boiler.
The pump is started in the following sequence:
a) turn on the fore-vacuum pump and, opening the valve, pump out the system
with a steam-oil pump up to a pressure of 5·10 -2 - 1·10 -2 mm Hg. Art.;
b) let in water to cool the pump housing;
c) turn on the electric heater of the steam-oil pump.
To stop the pump, turn on the electric heater of the pump and supply water to cool the bottom. After the pump has cooled, close the valve, turn off the fore-vacuum pump and stop the water supply.
Main characteristics of steam oil pump:
Maximum residual pressure no more than 5·10 -7 mm Hg. Art.
Pumping speed Fp 500 l/s
The maximum outlet pressure is not less than 0.25 mm Hg. Art.
Inflow of atmospheric air is no more than 0.02 l×mm Hg. st./s
Oil grade VM-1 GOST 7904-56
preliminary discharge VN-2MG or NVR-5D
PROCEDURE FOR PERFORMANCE OF THE WORK
1. Turn on the installation, for which the “network” machine is switched to the “On” position.
2. Turn on the mechanical pump by moving the switch knob to the “On” position.
3. Evacuate the volume of the steam-oil pump, open the lower valve of the valve box.
4. Turn on the steam-oil pump heater with the “On” toggle switch.
5. 35 - 40 minutes after turning on the steam-oil pump heater, turn on the nitrogen feeder.
6. After warming up the steam-oil pump, close the lower valve and perform preliminary pumping of the under-cap volume by opening the upper valve of the valve box.
7. Take and plot the P(t) characteristic during pumping on a mechanical pump; for this, record the readings of a thermocouple vacuum gauge every 10 minutes for one hour. Summarize the data in a table and draw a P(t) curve.
8. Remove and plot the characteristic P(t) for the diffusion pump. Conduct the experiment in the same way as in point 7.
9. Assess the capabilities of both pumps when the pre-vacuum level is reached: mechanical within 40 minutes, high-vacuum within 1 hour.
10. Give a conclusion about the preliminary vacuum that can be obtained with the proposed pumping system.
11. Present the data obtained during the experiment in the form of tables and graphs.
CONTROL QUESTIONS
1. How is vacuum classified? Explain the operating principle of the vacuum deposition installation and the purpose of the components.
2. Explain the correct sequence of turning on and off vacuum pumps in a vacuum installation. Explain how the maximum vacuum that can be obtained in such an installation is limited.
3. Explain the operation of a steam oil pump.
4. Explain the operation of a mechanical pump.
5. Explain the principle of vacuum measurement and the operation of thermionic and ionization sensors.
6. Explain the purpose and operation of the leak valve.
7. Explain the principle of operation and structure of nitrogen and electromagnetic traps.
8. Comment on the obtained vacuum characteristics of the installation.
Modification of various designs, parts and functional elements often performed by completely changing the structure of materials. For this purpose, means of deep thermal, plasma and chemical processing are used. But there is also a wide segment of methods for changing performance properties through external coatings. Such methods include vacuum metallization, thanks to which it is possible to improve the decorative, conductive, reflective and other characteristics of materials.
General information about the technology
The essence of the method is to spray metal particles onto work surface. The process of forming a new coating occurs due to the evaporation of donor metals under vacuum conditions. The technological cycle involves performing several stages of structural changes in the target base and coating elements. In particular, the processes of evaporation, condensation, absorption and crystallization are distinguished. The key procedure can be called the interaction of metal particles with the surface under conditions of a special gas environment. At this stage the technology vacuum metallization ensures the processes of diffusion and attachment of particles to the structure of the workpiece. At the output, depending on the spraying modes, coating characteristics and type of workpiece, a variety of effects can be obtained. Modern technical means make it possible not only to improve individual performance qualities of a product, but also to differentiate with high accuracy the properties of the surface in individual areas.
Equipment used
There are three main groups of machines used for this technology. These are continuous, semi-continuous and batch equipment. Accordingly, they differ in terms of the general organization of the processing process. Continuous units are often used in serial production where in-line vacuum metallization is required. Equipment of this type can be single- or multi-chamber. In the first case, the units are oriented towards performing metallization directly. Multi-chamber models also provide the possibility of implementing additional procedures - initial preparation of the product, control, heat treatment etc. This approach allows us to optimize the manufacturing process. Machines for batch and semi-continuous metallization usually have one main chamber. It is precisely because of the irregularity of production that they are used for a specific procedure, and preparatory operations and the same quality control are carried out in a separate order - sometimes manually without automated lines. Now it’s worth taking a closer look at what components such units consist of.
Design of machines for metallization
In addition to the main chamber, where the deposition processes take place, the equipment includes many auxiliary systems and functional components. First of all, it is worth highlighting the direct sources of the sprayed material, whose communications are connected to the gas distribution complex. In order for the vacuum metallization installation to provide the parameters necessary for a specific processing task, the deposition supply channels with regulators allow, in particular, to adjust the temperature level, flow speed and volumes. In particular, this infrastructure is formed by leaks, pumps, valves, flange elements and other fittings.
In modern installations, for the same regulation of operating parameters, sensors connected to a microprocessor unit are used. Taking into account the specified requirements and fixing the current ones actual values, the equipment can adjust processing modes without operator participation. Also, to facilitate operating processes, the equipment is supplemented with in-chamber cleaning and calibration systems. Thanks to such equipment, the repair of vacuum metallization of the machine is simplified, since constant and timely cleaning minimizes the risks of overloading pneumatic motors, manipulators and communication circuits. The latter are completely considered as a consumable part, the replacement of which in continuous units is carried out as part of regular maintenance.
Target materials for metallization
First of all, metal blanks, which can be made from special alloys, are subjected to the procedure. Additional coating is required to provide an anti-corrosion layer, improve the quality of electrical wiring or change decorative properties. In recent years, vacuum metallization has been increasingly used in relation to polymer products. This process has its own specifics, determined by the characteristics of the structure of objects of this kind. The technology is less commonly used for products that have low hardness values. This applies to wood and some synthetic materials.
Features of metallization of plastics
Spraying on the surface of plastic parts can also change its electrical, physical and chemical properties. Metallization is often used as a means of improving the optical qualities of such workpieces. The main problem when performing such operations is the process of intense thermal evaporation, which inevitably puts pressure on the flow of particles spraying the surface of the element. Therefore, special regimes for regulating the diffusion of the base material and the consumed mass are required.
Vacuum metallization of plastics, which have a rigid structure, also has its own specifics. IN in this case The presence of protective and priming varnishes will be important. To maintain a sufficient level of adhesion to overcome the barriers of these films, it may be necessary to increase the energy of thermal exposure. But here again the problem arises with the risk of destruction of the plastic structure under the influence of heat flows. As a result, to relieve excess tension in work environment Modifying components such as plasticizers and solvents are introduced to keep the shape of the workpiece in optimal condition, regardless of temperature conditions.
Features of processing film materials
Technologies for the production of packaging materials include the use of metallization for PET films. This process provides aluminization of the surface, due to which the workpiece is endowed with higher strength and resistance to external influences. Depending on processing parameters and final coating requirements, different ways heat sink. Since the film is temperature sensitive, an additional deposition procedure is introduced. As with plastics, it allows you to adjust the thermal balance, maintaining an optimal environment for the workpiece. The thickness of films processed using the vacuum roll metallization method can range from 3 to 50 microns. Technologies are gradually being introduced that provide similar coatings on the surfaces of materials with a thickness of 0.9 microns, but for the most part this is still only an experimental practice.
Metallization of reflectors
This is also a separate area of using metallization. The target object in this case is car headlights. Their design provides for the presence of reflectors, which over time lose their performance qualities - they fade, rust and, as a result, become unusable. In addition, even a new headlight can be accidentally damaged, requiring repair and restoration. It is precisely this task that vacuum metallization of reflectors is oriented towards, providing wear-resistant deposition on the mirror surface. Filling the external structure with metallized particles, on the one hand, eliminates minor defects, and on the other, acts as a protective coating, preventing possible damage in the future.
Organizing the process at home
Without special equipment, surface chemical coating technology can be used, but vacuum processing will in any case require an appropriate chamber. At the first stage, the workpiece itself is prepared - it should be cleaned, degreased and, if necessary, sanded. Next, the object is placed in a vacuum metallization chamber. You can also make special equipment on rails from profile elements with your own hands. This will be a convenient way to load and unload material if processing is planned on a regular basis. So-called ingots are used as a source of metallization particles - made of aluminum, brass, copper, etc. After this, the camera is adjusted to optimal mode processing and the spraying process begins. The finished product immediately after metallization can be coated manually with auxiliary protective coatings based on varnishes.
Positive feedback about the technology
The method has many positive qualities, which are noted by users of finished products in various fields. In particular, the high protective properties of the coating are indicated, which prevents corrosion and mechanical destruction of the base. Ordinary consumers also respond positively to products that have been subjected to vacuum metallization in order to improve or change their decorative qualities. Experts also emphasize the environmental safety of the technology.
Negative reviews
The disadvantages of this method of processing products include the complexity of the technical organization of the process and high requirements for preparatory measures for the workpiece. And this is not to mention the use of high-tech equipment. Only with its help can you obtain high-quality spraying. Cost is also included in the list of disadvantages of vacuum metallization. The cost of processing one element can be 5-10 thousand rubles. depending on the area of the target area and the thickness of the coating. Another thing is that serial metallization reduces the cost of an individual product.
Finally
Changing the technical, physical and decorative properties of certain materials expands the possibilities for their further use. The development of the vacuum metallization method led to the emergence of special areas of processing with a focus on specific performance qualities. Technologists are also working to simplify the deposition process itself, which is already manifested today in the form of a reduction in the size of equipment and a reduction in post-processing procedures. As for using the technique at home, this is the most problematic method of coating, since it requires the performer to have special skills, not to mention technical means. On the other hand, more available methods Spraying does not allow obtaining coatings of the same quality - be it a protective layer or decorative stylization.
To acquire a marketable appearance and certain technical properties in modern production, all finished products are coated various materials. This issue is especially relevant for metal parts, where the coating plays not so much a decorative role as it protects the metal from corrosion and other harmful environmental factors.
Vacuum spraying
In modern production, the most advanced technology for applying coatings to parts is vacuum deposition. The technology consists of direct condensation of vapor from the applied coating onto the surface of the part. There are three main stages of such spraying:
Evaporation of the substance from which the coating will be created;
Transfer of the created steam to the surface on which the substance will be applied;
Condensation of steam onto the surface of a part and creation of a coating from it.
Installation for chrome plating of alloy wheels
Vacuum deposition methods
In addition to vacuum, other physical processes can also be involved in sputtering. The classification below will also apply to substances that will be sprayed onto the surface.
Vacuum plasma spraying
Vacuum-arc coating is carried out according to the following mechanism. The cathode is the surface on which the film must be applied, and the anode is the gas discharge substrate. When the arc heats the atmosphere to the maximum temperature, the sputtering material transitions into the gaseous phase and is transferred to the cathode. Then the spray molecules condense on the surface of the product, forming a homogeneous layer. Uniformity in vacuum-arc spraying installations can be adjusted until the initial product with spray patterns is obtained.
This complex technology is used to apply super-hard coatings to cutting and drilling tools. Strong, wear-resistant drill bits for rotary hammers are created using vacuum plasma spraying.
High-strength hammer drills
Ion-vacuum sputtering
Considered the most environmentally friendly way to coat any metal surface. The downside is that the equipment is expensive; not every company can afford to purchase and install it.
Strict requirements are also imposed on surface cleanliness, however final result exceeds all expectations. The applied coating is characterized by high homogeneity, strength and wear resistance, therefore, in this way, coatings are sprayed onto parts and mechanisms that will be operated in harsh climatic conditions. This is the last operation after which further processing of parts is not allowed - there should be no welding or cutting.
Vacuum deposition of aluminum
Applying aluminum is considered the most popular method of metallization of almost any surface. The versatility of aluminum allows it to be applied to such unusual surfaces as plastic and glass, and, unlike other metals, it does not require an additional varnish coating for durability. Aluminum is usually used for decorative purposes - it is used for car accessories and headlight reflectors, cosmetic items, cabinet and door handles, and sewing accessories. Although this metal is not highly durable, the development of technology has greatly reduced the cost of such spraying, making it the most widespread in the world.
Aluminum Coated Car Headlight Reflector
Vacuum deposition of metals
In addition to aluminum, there are a number of equally common metals for spraying. Due to various physical and chemical properties they have found application in absolutely all industries. Main purposes of sprayed metals:
improved conductivity;
increased insulation;
imparting wear-resistant and anti-corrosion properties.
Regulating the temperature when applying a coating layer allows you to give the final product almost any shade; this is often used to apply “gold” coatings (nickel-titanium alloys are used).
Sputtering of titanium and silver is widely used in medicine. These unique metals interact very well with the human body and have antibacterial properties. Implants and surgical instruments (as well as dental and other) are coated with silver almost everywhere - a high guarantee of the strength and sterility of the instrument.
Vacuum ion-plasma sputtering
Under influence high temperatures the coating does not just condense on the surface of the part, it is literally baked on it, which gives the final product very high specifications– wear resistance under mechanical stress and good resistance to harsh weather conditions.
UVN vacuum spraying installation
Devices of the UVN type are modern high-tech vacuum deposition installations. Depending on the purpose, it can be equipped with any devices for evaporating the substance and transferring it to the surface of the part. Structure:
Process chamber closed type– the area where the part is placed, which is processed during the vacuum deposition process.
The control unit is a panel with buttons and controls that allow you to set all the necessary parameters before starting work. Modern options Vacuum spraying units are equipped with digital displays to display process parameters in real time.
The unit housing hides all the important mechanical and electronic components of the unit, protecting them from accidental and unauthorized intervention, as well as ensuring the safety of the machine operator. Depending on the size of the machine, it is equipped with wheels (with brake pads, for small models), or installed permanently (for powerful and productive cameras).
Classic UVN
