It has become an indispensable material in many industries. Aviation aluminum is a group of alloys characterized by increased strength with the inclusion of magnesium, silicon, copper and manganese. Additional strength is given to the alloy with the help of the so-called. "aging effect" - a special method of hardening under the influence of an aggressive atmospheric environment for a long time. The alloy was invented at the beginning of the 20th century, called duralumin, now also known as avial.

Definition. Historical digression

The beginning of the history of aviation aluminum alloys is considered to be 1909. The German metallurgical engineer Alfred Wilm experimentally established that if an aluminum alloy with a slight addition of copper, manganese and magnesium after quenching at a temperature of 500 ° C and rapid cooling is maintained at a temperature of 20-25 degrees for 4-5 days, it gradually becomes harder and stronger without losing ductility. The procedure was called "aging" or "maturing". During such hardening, copper atoms fill many tiny zones at the grain boundaries. The diameter of the copper atom is smaller than that of aluminum, therefore, a compressive stress appears, as a result of which the strength of the material increases.

For the first time, the alloy was mastered at the German factories Dürener Metallwerken and received trademark Dural, hence the name "duralumin". Subsequently, the American metallurgists R. Archer and V. Jafris improved the composition by changing the percentage, mainly of magnesium. The new alloy was named 2024, which is widely used in various modifications even now, and the entire family of alloys is called Avial. This alloy received the name "aviation aluminum" almost immediately after the discovery, since it completely replaced wood and metal in structures. aircraft.

Main types and characteristics

There are three main groups:

• Aluminum-manganese (Al-Mn) and aluminum-magnesium (Al-Mg) families. The main characteristic is high corrosion resistance, barely inferior to pure aluminum. Such alloys lend themselves well to soldering and welding, but are poorly cut. Not hardened by heat treatment.
• Corrosion-resistant alloys of the aluminum-magnesium-silicon system (Al-Mg-Si). They are hardened by heat treatment, namely, hardening at a temperature of 520 ° C, followed by rapid cooling with water and natural aging for about 10 days. A distinctive characteristic of this group of materials is their high corrosion resistance when used in normal conditions and under stress.
• Structural (Al-Cu-Mg). Their base is aluminum alloyed with copper, manganese and magnesium. By changing the proportions, an aviation one is obtained which may differ.

The materials of the last group have good mechanical properties, but at the same time they are very susceptible to corrosion than the first and second families of alloys. The degree of susceptibility to corrosion depends on the type of surface treatment, which still needs to be protected by paint or anodizing. Corrosion resistance is partially increased by the introduction of manganese into the composition of the alloy.

In addition to the three main types of alloys, there are also forging high-strength structural and other alloys that have the properties necessary for a particular application.

Aviation alloy marking

In international standards, the first digit of the aviation aluminum marking indicates the main alloying elements of the alloy:

• 1000 - pure aluminum.
• 2000 - duralumins, alloys alloyed with copper. In a certain period - the most common aerospace alloy. Due to their high susceptibility to stress corrosion cracking, they are increasingly being replaced by 7000 series alloys.
• 3000 - alloying element - manganese.
• 4000 - alloying element - silicon. Alloys are also known as silumins.
• 5000 - alloying element - magnesium.
• 6000 are the most ductile alloys. Alloying elements are magnesium and silicon. They can be heat-hardened to increase strength, but are inferior to the 2000 and 7000 series in this parameter.
• 7000 - thermally hardened alloys, the most durable aviation aluminum. The main alloying elements are zinc and magnesium.

The second digit of the marking is the serial number of the modification of the aluminum alloy after the original one - the number "0". The last two digits are the number of the alloy itself, information about its purity by impurities. If the alloy is experimental, a fifth “X” sign is added to the marking.

To date, the most common grades of aviation aluminum are: 1100, 2014, 2017, 3003, 2024, 2219, 2025, 5052, 5056. Distinctive features These alloys are: lightness, ductility, good strength, resistance to friction, corrosion and high loads. In the aircraft industry, the most widely used alloys are 6061 and 7075 aircraft aluminum.

Compound

The main alloying elements of aviation aluminum are: copper, magnesium, silicon, manganese, zinc. The percentage of these elements by weight in the alloy is determined by such characteristics as strength, flexibility, resistance to mechanical stress, etc. The base of the alloy is aluminum, the main alloying elements are copper (2.2-5.2% by weight), magnesium (0. 2-2.7%) and manganese (0.2-1%).

A family of aviation alloys of aluminum with silicon (4-13% by weight) with a small content of other alloying elements - copper, manganese, magnesium, zinc, titanium, beryllium. Used to make complex parts, also known as silumin or cast aluminum alloy. The family of aluminum-magnesium alloys (1-13% by weight) with other elements have high ductility and corrosion resistance.

The role of copper in aircraft aluminum

The presence of copper in the composition of the aviation alloy contributes to its hardening, but at the same time has a bad effect on its corrosion resistance. Dropping out along the grain boundaries during the quenching process, copper makes the alloy susceptible to stress and intergranular corrosion. Copper-rich areas are more galvanically cathodic than the surrounding aluminum matrix and are therefore more vulnerable to galvanic corrosion. An increase in the copper content in the mass of the alloy up to 12% increases the strength properties due to dispersion strengthening during aging. With a copper content in the composition of more than 12%, the alloy becomes brittle.

Applications

Aluminum alloys are the most sought after metal for sale. The light weight of aircraft-grade aluminum and its strength make this alloy a good choice for many industries from aircraft to household items ( mobile phones headphones, flashlights). Aluminum alloys are used in shipbuilding, automotive, construction, railway transport, and the nuclear industry.

Alloys with moderate copper content are widely demanded (2014, 2024 etc.). Profiles made of these alloys have high corrosion resistance, good machinability, and spot weldability. Responsible structures of aircraft, heavy vehicles, military equipment are made from them.

Aircraft aluminum connection features

Welding of aviation alloys is carried out exclusively in a protective environment of inert gases. The preferred gases are: helium, argon or a mixture thereof. Helium has a higher thermal conductivity. This determines more favorable temperature indicators of the welding environment, which makes it possible to quite comfortably connect thick-walled structural elements. The use of a mixture of protective gases contributes to a more complete gas removal. In this case, the probability of formation of pores in weld decreases significantly.

Application in aircraft industry

Aviation aluminum alloys were originally specially created for the construction of aviation equipment. Aircraft bodies, engine parts, chassis, fuel tanks, fasteners, etc. are made from them. Aviation aluminum parts are used in the interior of the cabin.

Aluminum alloys of the 2xxx series are used for the production of parts exposed to high temperatures. Parts of lightly loaded units, fuel, hydraulic and oil systems are made of 3xxx, 5xxx and 6xxx alloys. Alloy 7075 has received the widest application in the aircraft industry. Elements are made from it for operation under significant load, low temperatures with high resistance to corrosion. The basis of the alloy is aluminum, and the main alloying elements are magnesium, zinc and copper. Power profiles of aircraft structures, skin elements are made from it.

June 4th, 2012

Original taken from sergeydolya in How airplanes are made. Part 2

If in the previous workshop of Sukhoi, the plane was literally planed out of a piece of aluminum, then in the workshop, which I will talk about today, they breathe life into it. Here the aircraft is given wings, avionics, engines and interior, after which it takes to the skies for the first time in its life...

The first thing that catches your eye in the final assembly shop of the Superjet is the perfect cleanliness and order:

There are lightboxes next to each aircraft, reporting on the specific work being done at the moment with each of the 6 aircraft in the hangar:

The workshop is cleaned 4 times a day - dirt and the plane are incompatible:

All assembly processes are controlled from fenced areas - exactly the same I saw at the Boeing factory:

In the final assembly shop, 6 aircraft are being built at the same time, plus one is ready-made until it is accepted and taken away by the customer:

The plant works on the conveyor principle. The workshop has 6 workplaces, each of which the aircraft spends 30 days. This is the so-called "production cycle":

At the first workplace, or on "Platform No. 1", vertical and horizontal tails, doors, luggage hatches, a keel and a stabilizer are installed, an electric wire and a pipeline are installed through which fuel and hydraulic fluid are supplied to hydraulic systems (although here the aircraft looks like an eared helmet Dart Veder?):

Upper Antennas:

In the cockpit of the aircraft, the first wires are pulled and a system for supplying a water-repellent liquid, a windshield cleaning system are installed.:

Mount the cover of the auxiliary power unit (APU), which is used to start the main engines and to provide the aircraft with energy in the parking lots:

Center section - the central part of the aircraft, to which the wings will be attached during the next cycle. When the plane is built, this section will be pressurized and, like the wing part, will have a fuel tank:

At the second workplace, the wings are attached to the aircraft, the landing gear is hung, the APU itself and the front fairing are mounted:

The SSJ100 is the first Russian aircraft to dock automatically. The fuselage of the aircraft is leveled, and the wings are raised on special jacks. Everything is aligned with a laser, after which the wing is docked and attached to the fuselage:

The landing gear is attached after the wings are installed. They should be removed into the cavity under the aircraft behind the center section. After installing the landing gear, the aircraft moves from one workplace to another already on its wheels:

Chassis withstand 70 thousand takeoffs and landings:

The Superjet has 83 kilometers of wires. Girls are mainly engaged in sealing electrical connectors and dialing:

I don’t understand how they understand these wires, but knowledgeable people say that it’s impossible to confuse:

A protective cover is put on each harness with a marking that prevents dust from entering and indicates the order of docking:

The aircraft from the inside is "upholstered" with mats of heat and sound insulation:

Near each opening in the floor there is a warning sign:

During the third stroke, engine mounting pylons are hung on the wing, slats, flaps are installed, electrical connections are closed:

Charming girls clean the upper wing panel from excess sealant:

During the fourth stroke, the hydraulic system and the air conditioning system are mounted, all kinds of leaks are detected, the wing-fuselage fairing frame is mounted, the fuselage is pressurized with excess air pressure from a special stand, and electronic equipment is installed:

On the 5th cycle, the aircraft is "put under current", that is, they begin to test all on-board systems under current:

Technical panels in the floor are opened, and workers lay wires through the luggage compartment, mount the cable network:

There are several such compartments on board - both under the cabin floor (cabin space) and in the front / rear luggage compartments. Actually, the whole complexity of a modern aircraft is like such a bunch of different equipment cram it into a rather limited space and make it work flawlessly and without unnecessary interference:

The master controls the implementation of design changes:

At the final 6th cycle, the cabin, engines, cockpit are mounted on the aircraft, general inspection and roll-out are carried out - that is, the aircraft is rolled out of the hangar for the first time, where it is transferred to the flight test station:

Until the completion of the work, the salon is closed with special covers so as not to damage it before delivery to the customer. Pay attention to the legroom for passengers in the first row of economy class. If you ever fly a Superjet, ask for the front row:

Aircraft are equipped with Russian-French SaM146 engines:

The engines are optimized for 75 seats, but most airlines prefer to book cabins with 95 seats, because of this there was an opinion that the Superjet had weak engines. At the moment, Sukhoi is working on increasing engine power by 5% for the long range version of the aircraft, which will inevitably lead to an increase in the cost of its maintenance and a reduction in resource:

Testing systems before the first flight:

After flight test work, the aircraft flies to Ulyanovsk, where it is painted, and after that it is returned to Komsomolsk-on-Amur for final finishing and elimination of all minor problems:

Currently, each aircraft is produced in 180 days. The factory is faced with the task of speeding up production so that the construction of the aircraft takes 54 days.

If at the moment 1 production cycle is 30 days, then this means that Sukhoi produces 1 aircraft every month. In the future, each cycle will be reduced to 9 days, which will allow the production of 3 aircraft per month.

At the moment, 11 aircraft have already been built, but it is not enough to design and produce an aircraft, it still needs to be tested (to prove that it turned out to be a worthy product) and certified, because. it is a new type of aircraft. Without certificates, no airline will buy - why a plane that cannot carry passengers?

The 1st, 3rd, 4th and 5th SSJ100 aircraft are based at the flight test complex of CJSC "GSS" at the Gromov Flight Research Institute in Zhukovsky.
2nd - in TsAGI, Zhukovsky
6th - in SibNIA, Novosibirsk

The 1st SSJ100 (serial number 95001, tail number 97001) made its first flight on May 19, 2008, and in October 2008 began flight certification tests. Due to the fact that the "one" does not fully correspond to the typical design of the SSJ100, he took part mainly in aerodynamic tests and tests for critical conditions (icing, stalling).

2nd SSJ100 (serial number 95002, no tail number - because it did not fly) in TsAGI (Central Aerohydrodynamic Institute named after Zhukovsky) on static tests. The aircraft is loaded and they look at what happens to the structure - how it behaves, how it withstands.

The 3rd flying prototype (95003, 97003) passed, for example, performance tests, stability and control, crosswind tests in Iceland last year.

4th (also flying - 95004, 97004) - fail-safe tests, tests of all aircraft systems, 1st stage of tests at high temperatures, tests under high-intensity electromagnetic fields, tests at high mountains.

5th (flying - 95005, 97005) - tests at high temperatures, tests at low temperatures, also fail-safe and also tests of all systems.

6th (non-flying - 95006) - is being tested for a resource - laboratory flights are being carried out on it.

The 7th SSJ100 (serial number 95007, tail EK-95015 (Armavia) is the first production aircraft. Named after Yuri Gagarin. The first commercial flight was made on 04/21/2011, since then it has flown more than 1000 hours.

The 8th SSJ100 (95008, airborne RA-89001 (Aeroflot) - named after Mikhail Vodopyanov. The first flight was made on 06/16/2011 on the route Moscow - St. Petersburg.

9th SSJ100 (95009, no airborne yet, because it was not handed over to Armavia) - Armavia plans to put the aircraft only in the summer schedule, so its production has been suspended for now in order to speed up work on aircraft for Aeroflot.

10th SSJ100 (95010, RA-89002) - 2nd SSJ for Aeroflot - named after Dmitry Yezersky. The first flight was made no later than August 27, 2011.

The 11th is the one we saw in the final assembly shop.

To date, Sukhoi has pre-orders for 168 aircraft, that is, production will be loaded until 2015:

Aeroflot - 30
VEB-leasing for UTair - 24
Interjet (Mexico) - 15
Gazprom - 10
FLC for Yakutia - 2
Armavia - 2
Kartika Airlines (Indonesia) - 30
Phongsavanh (Laos) - 3
Pearl Aircraft Corporation (USA) - 30
Blue Panorama Airlines (Italy) - 4
Willis Lease Finance Corporation (USA) - 6
Sky Aviation (Indonesia) - 12

The catalog price of the Superjet is $31.7 million. Of these, the cabin seats alone cost $1.2 million. Engines cost 25% of the cost of the aircraft.

The main competitors of the Sukhoi Superjet are Embraer E-190, Bombardier CRJ900-1000 and AN-158.

We just caught the moment when the 11th aircraft was handed over to Aeroflot. Here is what the serial Sukhoi Superjet 100 looks like:

Luggage compartment:

The layout of the seats in the cabin 3 + 2:

The distance between the rows in economy class is 79 centimeters, in business class - 97 centimeters:

As I already wrote, the passengers of the first row of the economy class have the most legroom:

In the business class, the layout of the seats is 2 + 2:

Kitchen at the tail of the plane:

Absolutely not soviet, large and comfortable toilet:

Well, the handsome plane itself:

There is an opinion that the Sukhoi SuperJet100 is not OUR aircraft, that it is simply assembled from foreign parts, and thus, we should not be proud of it. However, all the brains that designed it are ours, and our design bureau, and our plant. What to do if our industry is not yet able to produce components of the quality that are necessary for the production of a world-class aircraft.

So the Superjet can rightfully become the point of revival of the Russian aviation industry!

Candidate of Technical Sciences A. ZHIRNOV, Deputy CEO VIAM.

Science and life // Illustrations

Science and life // Illustrations

The eight-engine giant ANT-20 ("Maxim Gorky") was built, like many metal aircraft of the early 1930s, from corrugated aluminum.

When using the traditional D-16 alloy, the Tu-154 passenger aircraft turned out to be too heavy.

The welded body of the MiG-29 aircraft is made of aluminum-lithium alloy 1420.

Massive and very important parts of the chassis of modern transport and passenger aircraft of OKB im. S. V. Ilyushin are made of titanium alloy VT-22. In the photo: IL-76.

Steel and aluminium, titanium and plastics, adhesives and wood, glass and rubber - no aircraft can fly without these materials. All of them are developed or tested in VIAM

The most advanced metallurgical technologies are embodied in each blade of a jet engine turbine. The cost of one monocrystalline blade is commensurate with the price of an expensive car

The testing center is the "small academy of sciences" of VIAM. Does metal fatigue threaten to destroy an aircraft? How to find hidden defects in metal? What properties does new material? The employees of the Test Center understand all this.

Arm wrestling as a way to resolve a scientific dispute, or How N. S. Khrushchev flew to America

- "Aged" material does not mean "old"

How to cut a "fur coat" for "Buran"

Turbine blades are protected from high temperatures by plasma

The more perfect the aircraft, the more non-metallic materials it contains. Planes have already been designed, two-thirds consisting of composite materials and plastics

Laboratory assistant in the morning, student in the evening. And all this - without leaving the native laboratory. If the state does not train specialists, they have to be trained on the spot

Corrosion is the enemy of any metal. Even stainless steel rusts. How to treat ulcers on the body of "Worker and Collective Farm Woman"?

You can glue anything. All you need is the right glue. Glued planes fly in the sky, and these are not children's models, but large transport aircraft.

The first steps of our aviation are connected with the purchase of foreign aircraft. They were mostly wooden, the fuselage and wings were covered with fabric. Of course, such "cloth" aircraft could not withstand significant speed and temperature loads, other materials were needed, primarily metal.

The idea to build aircraft from aluminum originated in Germany. The first alloys designed specifically for aircraft appeared there. They were called Duralumins. A similar alloy was created in our country in the mid-20s. He received the brand D-1 - an alloy of aluminum with copper and a small amount of magnesium.

In 1932, Academician A. A. Bochvar developed the theory of recrystallization of aluminum alloys, which formed the basis for the creation of light alloys. By that time, there was a production base in the country: the first aluminum plant "Kolchugaluminy" (located in the village of Kolchugino, Vladimir Region) produced smooth and corrugated sheets of technical aluminum - this is aluminum with small additions of manganese and magnesium. Such aluminum had sufficient strength, was ductile, and therefore was used for sheathing the fuselages of aircraft.

However, the material for the new high-speed aircraft had to have completely different qualities. And some time later, in the laboratory of aluminum alloys of VIAM (created simultaneously with the opening of the institute in 1932), the D-16 alloy was developed, which was used in aircraft construction almost until the mid-80s. It is an aluminum-based alloy with a content of 4-4.5% copper, about 1.5% magnesium and 0.6% manganese. Almost any aircraft parts could be made from it: skin, power set, wing.

But the speed and altitude of flights grew. High-strength alloys were required. In the mid-1950s, Academician I. N. Fridlyander, who headed the laboratory of aluminum alloys, together with his colleagues V. A. Livanov and E. I. Kutaytseva, developed the theory of alloying high-strength alloys. The introduction of zinc and magnesium into the aluminum-copper system made it possible to sharply increase the strength of the material. This is how the V-95 alloy appeared, which has a strength of 550-580 MPa (~ 5500-5800 kgf / cm 2) and at the same time has good ductility. He had one flaw: insufficient corrosion resistance, which, however, was eliminated by two-stage artificial aging.

The new alloy was not immediately recognized by aircraft manufacturers. At this time, A. N. Tupolev created a new passenger liner Tu-154. The project did not fit into the specified weight characteristics in any way, and then the general designer himself called Friedlander, asking for help, to which he, of course, suggested using a new alloy. The project of the new car was reworked. Alloy B-95 found its way into the upper surface of the wing, and molded panels and stringers were made from it, significantly reducing the weight of the aircraft. Similar studies were going on in parallel in the USA. Alloys of the 7000 series appeared there, in particular, alloy 7075 is a complete analogue of our alloy.

The loads that an aircraft wing experiences are unequal. If the top of the wing works mainly in compression, then the lower part works in tension. Therefore, it was still made from D-16 duralumin, which has higher ductility and fatigue threshold. But even this alloy has undergone a serious modification by increasing the purity of impurities during casting of ingots. Technological improvements were so significant that actually a new material appeared - alloy 1163, which is currently successfully used in the lower wing skins and the entire fuselage.

Increasing the operational life of aircraft has always been and remains the number one task. It is possible to achieve even greater reliability and durability of materials by changing the structure of the metal - "grinding the grain". For this, small amounts (up to 0.1%) of zirconium were introduced into the alloys. The grain size of the metal really decreased sharply, the resource increased. At the same time, special forging alloys were created, designed for the most critical, load-bearing structures of liners. This is how the 1933 alloy was developed, which surpasses foreign analogues in its parameters. Parts of the power set and frames are made from it. Experts from the European aircraft manufacturer Airbus tested the new material and decided to use it in their A-318 and A-319 series aircraft.

Unfortunately, the process of very beneficial cooperation has been put on hold. The reason is that the shares of the two major Russian manufacturers aluminum products - Samara and Belokalitvensky metallurgical plants - were bought out by the American company "ALKO". A significant part of the equipment at the enterprises has been dismantled, the technological chain has been broken, qualified personnel have dispersed, and production has actually ceased. Now these enterprises produce mainly foil, which is used for the manufacture of food cans and packaging ...

And although at present, through Russian government between the company "ALCOA-RUS" (it is now called so), VIAM and aviation design bureaus, agreements were reached on resuming the production of materials so necessary for our aviation industry, the recovery process is extremely slow and painful.

VIAM became the ancestor of a series of low density alloys. It's perfect new class materials containing lithium. The first such alloy was created by academician I. N. Fridlyander with his students back in the 60s - a quarter of a century earlier than anywhere else in the world. Its practical use, however, was initially limited: such an active element as lithium requires special smelting conditions. The first industrial aluminum-lithium alloy (its grade 1420) was created on the basis of the aluminum-magnesium system with the addition of 2% lithium. It was used in the design bureau of A. S. Yakovlev in the construction of vertical take-off aircraft for carrier-based aviation - it is for such structures that saving weight is of particular importance. The Yak-38 is still in operation, and there are no complaints about the alloy. Furthermore. It turned out that parts made of this alloy have increased corrosion resistance, although aluminum-magnesium alloys themselves are little susceptible to corrosion.

Alloy 1420 can be welded. This property was used to create the MiG-29M aircraft. The gain in weight during the construction of the first prototypes of the aircraft due to the reduced density of the alloy and the exclusion of a large number of bolted and riveted joints reached 24%!

At present, Airbus specialists are very interested in the modification of this alloy - alloy 1424. At the plant in the city of Koblenz (Germany), wide sheets 8 m long were rolled out of the alloy, from which full-size fuselage structural elements were made. Stiffeners made of the same material were welded by laser welding, and the elements were joined together by friction welding, after which they were sent for life tests in France. Despite the fact that some parts were intentionally damaged (to assess performance in an extreme situation), after 70 thousand load cycles, the design completely retained its operational properties.

Another lithium alloy created at VIAM is 1441. Its main feature in that it is possible to make sheets of rolled rolling with a thickness of 0.3 mm from it while maintaining high strength qualities. The Beriev Design Bureau used the alloy to make the skin of its Be-103 seaplane. This small - only for four people - car, the skin thickness of which is 0.5-0.7 mm, is produced by a plant in Komsomolsk-on-Amur. Its weight is 10% less than similar models made of traditional materials. A batch of such aircraft has already been bought by the Americans.

Thin, but strong rolled products are needed to create a new class of materials that has recently appeared - laminated aluminum-glass-reinforced plastics, which are called "sial" in Russia, and "glair" abroad. The material is a multilayer structure: alternating layers of aluminum and fiberglass. It has many advantages over monolithic ones. Firstly, fiberglass can be reinforced with artificial fibers, increasing strength by a third. But the main advantage is that if a crack appears in the structure, it grows an order of magnitude slower than in monolithic materials. This is what sials, or glairs, first of all interested aircraft manufacturers in. For the first time, the upper part of the fuselage skin of the Airbus A-380 was made from such material in the most critical places - in front of the wing and after the wing. Resource tests showed that the crack in such a material practically does not grow under working loads. Therefore, glares can be used as stoppers to prevent the growth of cracks in the form of inserts in the upper fuselage skins, where particularly high reliability and a long service life are required.

Titanium, like aluminum, also has the right to be called heavenly or winged. The laboratory of titanium alloys was established at the institute in 1951. Its founder, Professor S. G. Glazunov, invented a titanium casting plant and, in fact, created the first titanium alloy. The second such installation was built with the help of VIAM at the All-Union Institute of Light Alloys (VILS), and then together we implemented the developed technological processes at the metallurgical plant in Verkhnyaya Salda, which is now the main producer of titanium products in the country. In Soviet times, the plant produced more than 100 thousand tons of such products. After the collapse of the USSR, production decreased several times. The new director of the plant, V.V. Tyutyuhin, had to make great efforts to rectify the situation. After a sharp decline in production, the plant began to rise. Now the output of titanium products is 25 thousand tons per year. Most of it (about 80%) is supplied abroad on orders from leading aircraft manufacturing concerns. In connection with the revival of the aircraft industry in Russia, there was an urgent need to create an alternative production. It is unprofitable for a giant, such as the plant, to produce small batches of products. The orders of Russian aircraft manufacturers are still small - 3-5 tons, and the manufacturing cycle is very long and reaches up to a year. Such production can be created on the basis of VIAM, VILS and the Stupino metallurgical plant, where, in fact, ingots obtained from Verkhnyaya Salda are processed.

More than fifty titanium alloys for various purposes have been created at VIAM, of which about thirty are used in series today. Now the proportion of titanium alloys in an aircraft, depending on its type and purpose, ranges from 4 to 10-12%. High-strength titanium alloys, such as VT-22, have been used for more than a quarter of a century for the manufacture of welded chassis of the Il-76 and Il-86. These complex, massive parts in the West are starting to be made of titanium only now. In rocket technology, the proportion of titanium is much higher - up to 30%.

High-tech alloys VT-32 and VT-35 created at VIAM are very plastic in the annealed state. They can be molded into complex parts, which, after artificial aging, acquire extremely high strength. When the Tu-160 strategic bomber was being created at the Tupolev Design Bureau in the early 1970s, a special workshop was built at the Moscow plant "Experience" for the manufacture of titanium parts of the center section. These planes are still flying, however, only one squadron of them remains in Russia.

Today, VIAM is faced with the task of creating titanium alloys that work reliably at temperatures of 700-750 o C. Unfortunately, all the metallurgical possibilities used to create traditional alloys have already been implemented. New approaches are required. In this direction, research is underway in the laboratory to create the so-called intermetallic compounds based on titanium - aluminum.

Aluminum-beryllium alloys (they are called ABM) have been researched and created at our enterprise for 27 years. The first aircraft using such an alloy was built by designer P. V. Tsybin.

ABM alloys favorably differ from other aluminum alloys in higher fatigue strength and unique acoustic endurance. Now they are used in welded structures spacecraft, including a series of well-known interplanetary stations "VENERA".

Beryllium itself is also interesting, in which the modulus of elasticity is 30-40% higher than that of high-strength steels, and the thermal expansion coefficients are close, which made it possible to use it in gyroscopes.

VIAM has developed a technology for manufacturing thin vacuum-tight foil and disks and plates from it. A technology has been developed for soldering such foil with other construction materials, and serial production of X-ray units has been launched both for Russian enterprises and for foreign firms.

Another branch of ours was organized in the Volga region in the early 1980s, during the creation of the largest aviation plant in Ulyanovsk, which produced aviation giants - Ruslans and Mriyas. For technological support these aircraft and a special laboratory was created.

One of its tasks is the introduction of composite materials into the aircraft industry. This is the near future of aircraft construction. For example, the Boeing 787, which is being prepared for production in two years, will consist of 55-60% composite materials. The entire airframe: fuselage, wing, plumage - is built from composite materials - carbon fiber. The share of aluminum will be reduced to 15%. CFRP is an extremely attractive material for aircraft builders. They have high specific strength, low weight, and fairly decent resource characteristics. The threat of destruction due to the formation of cracks is reduced by orders of magnitude. Although, of course, in relation to these materials there are a number of issues that have not yet been resolved. It was found, for example, that corrosion develops at the point of contact between carbon fiber and aluminum due to the occurrence of a galvanic couple. Therefore, in such places, aluminum had to be replaced with titanium.

When the Ulyanovsk branch was created, the share of composite materials in the design of domestic aircraft was not very large. Nevertheless, we slowly began to train technologists, workers… Then hard times came, the whole plant was on the verge of closing, but the branch survived. Gradually, production was restored, and although it is still half mothballed, there are several orders for the Tu-204, there are orders from Germany for the production of Ruslans. So, there is a field of activity for our laboratory.

The second line of work of the Ulyanovsk branch is special, erosion- and corrosion-resistant coatings.

During the decomposition of organometallic liquids in a vacuum, coatings of chromium and chromium carbides are formed on the surfaces. By adjusting the process, it is possible to obtain coatings containing any ratio of these components - from pure chromium to pure carbides. The hardness of the chrome coating is 900-1000 MPa, the hardness of the carbide coating is twice as high - about 2000 MPa. But, the higher the hardness, the greater the brittleness. Between these extremes and find the desired in each individual case.

Nanotechnology provides another way to achieve the desired results. Nanoparticles of carbides and metal oxides with a size of 50 to 200 nm are introduced into chromium-containing galvanic baths. The highlight of the process is that these particles themselves are not included in the composition of the coating. They only enhance the activity of the deposited component, create additional centers crystallization, due to which the coating is denser, more corrosion-resistant, has better anti-erosion properties.

And in conclusion, about one more unique quality of the institute: in the USSR there was a good system that reliably guaranteed the quality of the final product of the enterprise. In VIAM, this system has been preserved to this day. If a design bureau or a private company purchases a product, they prefer to submit it to VIAM for testing before use. We are still trusted.

See in a room on the same topic

Metals in the service of the fastest mode of transport.

In previous articles, we talked about the efficiency and benefits of using aluminum in the production of transport, including aviation.
What about other metals?

Magnesium. He found his place in the production of modern aircraft. Wheels and chassis forks, wing leading edges, seat parts, instrument cases, various levers and covers, cab doors and lights - and this is not the whole list of applications of magnesium alloys. Nowadays, magnesium has been actively used for the manufacture of cast wings, cast landing gear doors, which are lighter in weight by about 25% and cheaper than prefabricated structures made of wrought alloys. For example, the airframe of one of the American fighters was almost entirely made of magnesium-based alloys.

These cast magnesium alloys with rare earth additives are practically non-porous, and therefore parts made from these alloys are less susceptible to cracking.

Despite the fact that the elasticity of magnesium alloys is less than the elasticity of aluminum and iron alloys, due to the low density, this metal makes it possible to obtain more rigid and at the same time fairly light structures.

AT helicopter industry magnesium is used for the production of engines, in some models the proportion of magnesium parts is 23% by weight.

AT rocket science the most popular alloys in application are thorium and zirconium. They have earned such popularity due to their increased strength and heat resistance. Additive zirconium improves plastic properties. In some models, these alloys were 25% by weight.

They also introduce special alloys with zirconium, which have an important ability - to dampen the vibrations of projectiles,

When it comes to short-term structures, magnesium is also remembered during production, because due to its high heat capacity it is able to absorb a lot of heat and does not have time to overheat during a short flight.

The Folcon air-to-air missile consists of 90% magnesium alloys (body and many other parts). In addition to hull plating, tunnel fairings, guidance systems housings, pump housings, fuel and oxygen tanks, pneumatic system cylinders, support units, stabilizers, etc., cannot do without them.

AT satellite building of the alloys made make the body of the satellite. The body is made from two spherical shells stamped from 0.76 mm thick alloy sheets, and the whole structure is supported from the inside by a frame of magnesium pipes.

Due to the fact that magnesium sublimates noticeably in high vacuum at low temperatures, the body is covered with a complex coating, one of the purposes of which is to reduce metal evaporation.

Titanium. It is not only light and refractory metal, but also quite durable and ductile. The weight of titanium is two-thirds more than aluminum, the strength is 6 times greater, and the refractoriness of titanium is more than two times greater than that of aluminum.

It has good durability properties. In humid air, in sea water, its corrosion resistance is not worse than stainless steel, and in hydrochloric acid many times over. It, like stainless steel, can be processed by cutting and pressure, as well as welding and manufacturing cast parts from it.

The main advantages of titanium and its alloys, such as the combination of high specific strength and chemical resistance at normal and elevated temperatures (about 300-500º C), make them indispensable in modern aircraft and spacecraft manufacturing.

In 1956, the English pilot Peter Twiss on a supersonic aircraft made of aluminum alloys Fairy Delta-2 set a new world record for flight speed, reaching a speed of 1822 km / h at a distance of 15.5 km.

The power of the aircraft engine allowed it to develop even greater speed, but the pilot could not go for it, because if the record speed was exceeded, the aircraft skin made of duralumin would heat up to more than 100º C, and this would negatively affect the strength of the aircraft skin. Therefore, in order to achieve such huge speeds, the usual duralumin skin is changed to titanium, since it is not profitable to use heavier steel at such speeds and heatings.

When replacing aluminum alloys or steel with titanium in passenger aircraft, the savings in the mass of parts is approximately 15-40%. Despite the more expensive cost of titanium compared to the above metals, all additional costs pay off.

The example of Douglas passenger aircraft shows that at first only certain elements were made of titanium, such as engine nacelles and fire walls. In fire barriers, the use of titanium is effective, because the electrical and thermal conductivity of this metal is 5 times less than that of steel, and 15 times less than that of aluminum. But in the new aircraft models there were already more than 1000 different parts made of titanium and its alloys.

The use of titanium alloys in the production of jet aircraft engines makes it possible to reduce the weight by 100-150 kg. The glider also becomes lighter (by 300 kg or more).

In engines, titanium is used to make parts of the air collector, housing, compressor blades and disks, etc. The use of titanium in new turbofan engines has become particularly advantageous. In the civil aircraft model, titanium parts make up 1/7 of the total mass of the turbofan engine, in the military one - 1/5 of the total mass.

In rockets, titanium alloys are used to make engine cases for the second and third stages, cylinders and balloons for compressed and liquefied gases, nozzles, etc. The space capsules Mercury and Gemini have a frame, outer and inner skin made of titanium alloys.
Titanium in the form of cast parts is also actively used, as it allows to reduce the amount of labor cutting and reduces the waste of expensive metal.

As for the use of titanium in aviation electronics, then this metal is very useful due to its gas-absorbing abilities. It absorbs gases left after the device has been evacuated or which have entered the device during operation. Titanium deposited on the surface of the device acts as a built-in pump that can work throughout the life of the device. 500mg of titanium is enough to absorb large volumes of air.

Beryllium. For thin profiles, where titanium is not suitable due to its low specific rigidity, and steel and nickel alloys are very heavy, industrialists turn to a metal such as beryllium.

Its brittleness, toxicity of metal and oxide dusts, rarity and high cost are obstacles that delayed the use of beryllium in aircraft and rocket industries.

But after numerous studies that opened up the possibility of improving the necessary properties of this metal, beryllium was nevertheless adopted by manufacturers. Now rods, pipes and sheets are made from it for rocket, aviation and nuclear production.

Liquid-propellant housings made of beryllium are not only twice as light, but also last 10 times longer due to the high thermal conductivity of this material. Beryllium has become a godsend for wheel brake manufacturers due to its lightness and high thermal conductivity. Beryllium brakes provide a weight saving of more than 30%, the weight of the aircraft has decreased by more than 600 kg.

The same is true for fasteners, whose lighter weight does not prevent them from carrying the same loads as steel fasteners. The lower centrifugal stresses of compressor disks compared to disks made of other metals is another merit of beryllium. Less energy is wasted without changing the rotation speed.

To protect beryllium alloys from corrosion, anodizing methods are introduced. This makes it possible to noticeably increase the oxidation resistance at elevated temperatures (heat resistance).

It should also be noted that, due to its properties, beryllium absorbs heat well, and is a hyperconductor, conducting well electricity under low temperature conditions.

Alexander Rybakov
Sources used in writing the article:

Sh.Ya. Korovsky "Flying Metals"

For most people, airplanes evoke special emotions, admiration.

As a child, the child lifts his head, looking at a tiny dot in the sky, leaving a white trail behind him, at the airport, both children and adults love to cuddle up to the panoramic windows, watching the unhurried taxiing of aircraft along the apron, takeoff or landing, aircraft always take pictures and for a long time on they are being watched. It would seem that transport and transport, but no ...

There is no such mass reverence for cars, no for trains, for ships too ... but there is for airplanes. And everything connected with them. Maybe because a person can also move on land and water (walk and swim), but he can only go up to the sky by plane?

I have been many times to various industries - from small to gigantic, to unknown enterprises and factories of world famous brands, but I always dreamed of visiting where airplanes are made. The same planes that delight everyone, on which we all fly, which we photograph and admire.

Finally, my small dream came true, and last week I visited the main assembly facilities of the aviation giant Airbus in Toulouse, France, where I saw with my own eyes how airplanes are made.

1. If you, like me, love airplanes and want to see with your own eyes a little more than you are used to seeing at the airport, you need to get to the town of Blagnac, near Toulouse.

Here is the airport with the TLS code, which is both the Toulouse international airport and part of the huge Airbus factory. The airport and the plant have a common runway, so even sitting in a waiting room or a business lounge, you can quite see, in addition to the liners of several dozen airlines flying here, a lot of aircraft of the most unusual type, such as this Airbus A380 Qatari Airlines, which does not yet have a livery and is leaving for its first (!) test flight!

2. In general, everyone can get into the Airbus assembly shops! The company's factories in Toulouse and Hamburg organize 2-3 hour tours costing 10-15 euros. Keep in mind that for those wishing to get to the plant, a preliminary reservation is required. In addition, please note that taking pictures during such an excursion is strictly prohibited, both on any type of camera and on mobile phones, which is very strictly monitored by the escorts.

But we visited the Airbus factory not as part of a sightseeing tour, but spent two whole days here from morning to evening and without any prohibitions on photography.

In general, Airbus S.A.S is one of the largest aircraft manufacturing companies in the world, formed in the late 1960s through the merger of several European aircraft manufacturers. It produces passenger, cargo and military transport aircraft under the Airbus brand. The company's headquarters is located in the city of Blagnac (a suburb of Toulouse, France), as well as the main assembly facilities. At the same time, the company has four assembly sites - in Toulouse (France), Hamburg (Germany), Mobile (Alabama, USA), Tianjin (China).

At the factory in Toulouse, which will be discussed today, they collect all the lineup: A380, A350, A330/A330neo, A320/320neo. At the same time, A380, A350, A330 are assembled only at this plant.

3. First of all, let's go to the workshops where the company's most commercially successful aircraft is made - the A320 / A320neo series.

At one time, the A320 became a real hit and one of the most common aircraft of ALL currently in existence in the world. Since 1988, over 7,600 A320/A320neos have been produced, of which over 8,000 are currently flying.

It is estimated that every 1.4 seconds in the world one A320 lands or takes off somewhere, and if all the aircraft of this type produced are lined up, then its length will be 260 kilometers.

The full production cycle of one A320 (from the assembly of the first part to the delivery of the aircraft to the customer) is about a year, and the main components of the aircraft are made in 4 countries: the nose and front of the fuselage - in the French Saint-Nazare, the middle and rear fuselages - in Hamburg , the horizontal stabilizer - in the Spanish Getafe, the vertical stabilizer - in the German Stade, the wings - in the English Broughton, the flaps - in Bremen ...

All these parts are brought to one of the assembly sites, where the final assembly of the aircraft takes place, which takes about 1 month.

4. To the place of final assembly in Europe (and this is Toulouse and Hamburg), large aircraft elements - parts of the fuselage, wings and stabilizers are delivered by air, in the bowels huge transport aircraft Airbus Beluga.

This post already turns out to be very voluminous, so I will make a separate article about Beluga (meet him tonight).

5. This is what the rear fuselage of the A320 looks like, just unloaded from the huge Beluga near the final assembly line. At the same time, the passenger terminal of Toulouse-Blagnac Airport and the A330 just returned from a technical flight for the Chinese company Tianjin Airlines are clearly visible in the background.

6. The A320 final assembly line in Toulouse is located not just anywhere, but in the very hangars where the legendary Concorde were once assembled. You will be surprised, but on the basis of this fact, the hangars are even recognized as a historical monument!

On the one hand, this is cool and unique, on the other hand, it imposes certain restrictions on Airbus, since they cannot be rebuilt, changed, etc. It would seem that this is so? Just below you will understand)

7. We enter the hangars FAL - Final Assembly Line. It is here that the final assembly of the aircraft takes place, starting from the connection of the fuselage parts and ending with the "stuffing" - electronics equipment and installation of the interior.

Surprisingly, this strange greenish stump with a closed red fabric on the back is nothing more than a future aircraft.

8. In the front part, it looks a little more like the usual one - both the cockpit and the cabin windows are guessed. True, there are still no wings, no tail, no engines, no seats, no electronics.

9. By the way, the territory of the assembly shop is all divided into zones, each of which is drawn on the floor: zones for the location of the so-called assembly stations, zones for moving mobile equipment, and zones for moving people. It is impossible for a person without access to go beyond the red line. Only personnel working with a particular aircraft can be there.

10. Tail section of the future A320 and rear exit.

11. Place of attachment of the aircraft wing.

12. We pass to the next station. Here, the installation of wings, transverse and vertical stabilizers is already underway. Wings come without endings, mechanization, chassis and engines. All of this will be installed over the next few weeks.

13. Installation of a vertical stabilizer. By the way, it is the first to be painted in the colors of the livery of the airline for which this or that aircraft is assembled. As you understand, all aircraft are assembled to order from airlines according to a preliminary contract and never to a warehouse, as is the case with cars.

14. We move to the next station. Here the installation of the interior trim is carried out. Ready-made blocks with slots for portholes are visible in the boxes.

15. Porthole frames.

16. From the first FAL hangar, the aircraft enters with a fully assembled fuselage, wings installed, horizontal and vertical stabilizers, part of the cabin.

17. After that, the A320 leaves the first hangar and is moved to the next one, where the installation of engines, avionics, all electronics and the rest of the assembly takes place until the very end. But here there is one difficulty.

These are the historic hangars where Concorde was made. Those planes were much lower, but the tail of the A320 is much higher than the hangar opening (!), in the usual way it simply cannot be rolled out of here! But since the building is historical, it simply CANNOT be rebuilt or even cut through an opening for the passage of the aircraft stabilizer, as is often done. So the Airbus engineers had to come up with a special jack, with which they lift the front part and roll the plane out of the hangar, lowering the back part of the liner along with the tail to the very ground ...

18. Avionics and electronics mounting station. Here it was possible to catch the future Aeroflot board by the tail.

19. Do you know why airplanes in production have a red nose?

20. Very sensitive radar equipment is located under the nose cone, so a red film is applied to the nose, warning of special attention. Later, before painting, this film will simply be removed.

21. Almost at the very end, seats are installed in the aircraft according to the layout of the cabin chosen by the airline and the step between the seats.

22. Then engines are installed on the plane and painted in the airline's livery.

23. The engine of the modern A320neo. It is so huge that its diameter is larger than ... the interior of some business jets!!!

24. That's it, now the plane can be rolled out for flight tests! At the very end, there is a stage of "pre-sale" preparation and the process of handing over the aircraft to the customer. A commission comes from the customer and meticulously checks absolutely everything: both for the compliance of the aircraft with the selected specification, and for the functioning of everything, from sockets for passengers to engines and avionics. Then the acceptance flight and...

25. And that's it, the plane is being prepared for its first flight with the airline code, under which it will fly to the home airfield in Asia, Europe, the Middle East or Africa.

26. Not far from the A320 workshops, huge stabilizers in the colors of the world's best airlines rise - these are the latest A350, which began to be assembled not so long ago and which are just beginning to be massively distributed around the planet. Of course, the largest, richest, most famous airlines are the first to receive the novelty.

Along the way, we come across fuselage parts that are 1.5 times larger than the same parts for the A320. This is understandable, because it is already a wide-body long-haul aircraft, accommodating twice as many passengers and capable of covering much greater distances in the sky.

By the way, to assemble one A350, 7 (!!!) Beluga flights are needed. One brings the nose of the fuselage, the second - the middle, then the rear, tail and horizontal stabilizers, two wings (one flight for each), and one flight with various bulky parts of the aircraft.

28. The first thing that catches your eye on the A350 assembly line is the scale and spaciousness. These are already modern workshops with very high ceilings and a dozen aircraft being assembled at the same time.

29. During the assembly of the A350, they are no longer rolled from station to station, everything is assembled at one assembly site.

30. Wing attachment point. Fasteners of future highways, wire harnesses and various tubes are visible.

31. Slats.

32. Wing assembly without sharklet.

33. Emergency exit.

34. Horizontal stabilizer.

35. Front landing gear.

36. Equipment and aircraft parts come in such boxes.

37. Cockpit, front view.

38. Red nose A350.

39. Station FAL Airbus A350.

40. Assembled planes are rolled out into the street, where they wait for their turn in flight tests, and then sent for painting.

41. Already at the very end, leaving from assembly shop, we managed to see the landing A350-1000, the next version of the A350, which has not yet gone into production, but is only undergoing flight tests.