【Aluminium Network】Aircraft refers to various types of equipment that fly in the atmosphere 100km above the ground, such as aircraft, helicopters, unmanned aircraft, etc. Aircraft, also known as aircraft, can be broadly divided into two categories, military and military. Civil, but also military and civilian use. ARJ21, Xinzhou 60 regional airliner, C919 trunk airliner, AG600 amphibious airliner, etc., may be referred to as civil aircraft; bombers, fighter planes, attack aircraft, Y-20 heavy military transport aircraft are military, and may be referred to as military aircraft for short; Y- 20 It can also be used by both military and civilians, but it is mainly military. The trunk passenger aircraft can also be called a large aircraft. It refers to more than 100 aircraft with a voyage ≥ 5000 km.

ARJ Regional Airliner

ARJ21 is an abbreviation for the English name “Advanced Regional Jet for the 21st Century”, meaning a new generation of regional jet passenger aircraft in the 21st century. It is a 70-seat, mid- and short-range turbofan with a 90-seat launch and a new regional passenger aircraft. There are four brothers: basic type, extended type, freighter and business jet.

The ARJ21 civilian passenger aircraft is the first independently designed and manufactured regional passenger aircraft in China. The various parts of the aircraft are produced at four domestic aircraft manufacturing companies. A large number of internationally advanced technologies and airborne systems are used. Engines, avionics, and power supply systems are all competitively sourced and purchased worldwide. Many of these components are Made in China, there are also some products that are divided by China.

In April 2002, the ARJ21 aircraft project was formally established. In August, AVIC Commercial Aircraft Co., Ltd. was established to take charge of the operation of the project. The overall design of the project was carried out by the engineering department. In early 2003, the preliminary design and detailed design were transferred to China’s first-aviation front aircraft design research. hospital. In December 2003, ARJ21-700 manufactured parts and components at Chengdu Aircraft Co., Ltd., Shenyang Aircraft Co., Xi'an Aircraft Co., and Shanghai Aircraft Co., Ltd. at the same time. On December 21, 2007, the assembly line was erected at the Shanghai Aircraft Manufacturing Plant. In November 2008, Shanghai successfully made its first flight and completed its first flight demonstration flight in March 2015.

On November 29th, 2015, the 106th aircraft was piloted by Chengdu Airlines with excellent technology and experienced ARJ21 flight qualification. It flies from Shanghai China COMAC Airport to Chengdu Shuangliu Airport and delivers Chengdu Airlines. In March 2016, it was launched on the market and initially invested in 7 routes from Chengdu to Beijing, Shanghai, Guangzhou, Shenzhen, Wuhan, and Xi'an. From then on, the Made in China jetliner aircraft with all independent intellectual property rights for the first time was the history of China’s aviation industry. A special event. The ARJ21-700 regional airliner was officially launched from April 2002 to March 2016 and lasted 14 years.

ARJ21 passenger aircraft

Which aluminum and aluminum materials are used?

On January 23, 2017, Xu Lejiang, Deputy Minister of Industry and Information Technology, pointed out at the annual work conference on upstream and downstream cooperation mechanism of aluminum materials for civil aircraft that the Ministry of Industry and Information Technology must work out a key work plan for 2017 as soon as possible, and that production units should be strengthened in accordance with airworthiness certification requirements. Continue to tackle key issues, accelerate the development and application of key grade aluminum materials, and strive to achieve phased progress in 2017.

The ARJ21 regional airliner is basically made of aluminum alloy. The quality of the aluminum parts exceeds 75% of the net aircraft mass. Almost all of the commonly used aluminum alloys are used, but some are used more often and some are used less often. Is a deformed aluminum alloy, or cast aluminum alloy, almost all of the Department of alloys are used, a large four or fifty kilograms of skin panels, small rivets in grams, but the number is many, up to more than 40 Ten thousand. The total number of parts of the ARJ21 passenger aircraft is more than a million, but there are more fasteners, and it is the ancient rivets that are seated before the fasteners. Rivets have been available for thousands of years and have been used on airplanes for 112 years.

The 2xxx series and 7xxx series alloys are used more widely in the main aluminum structures of the ARJ21 regional passenger aircraft, and they are all newer generations of alloys. The aluminum used in the prototypes used in manufacturing forensics is provided by Alcoa. Wanliqian came to China across the ocean from the west coast of the United States. The plate was from Davenport Works in Iowa. Extrusion materials and forgings were produced by Lafayette Works. Some extruded materials are from Korea's Changguang Aluminum Corporation, which is a wholly-owned aluminium extrusion company of Alcoa in South Korea. The 2xxx and 7xxx series alloys accounted for 98% of the total amount of ARJ21 main structural aluminum. The reason why the prototype forensics machine was not manufactured with aluminum materials in China was to obtain a certificate of airworthiness, not to say that China could not manufacture 1kg. With the acquisition of airworthiness certificates, the use of domestic aluminum materials will increase year by year.

The deformed aluminum alloy 2524-T3 used in the ARJ21 regional passenger plane accounts for about 60% of the total amount of the board; followed by the 7050, 7150, and 7055 of the 7xxx series alloys, which account for about 35%, all of which are applied in the T77 state. T7 indicates the solid solution. After the aging treatment, the strength of the material is lower than the larger value it may reach, but the stress corrosion cracking resistance and intergranular corrosion resistance are greatly improved.

In addition, a small amount of titanium alloy sheet is also used. Ti-6Al-4V alloy is a more commonly used titanium alloy, and it is also an alloy with lower price and better overall performance.

Full use of 2524-T3 alloy skin

The 2524-T3 alloy is a very beefy 2xxx alloy. All skins of the ARJ21-700 regional airliner are all covered. They are all made of pre-stretched panels, including: fuselage skin, rear fuselage. Leather, wing under fuselage skin, fuselage skin grafts with wing, flap skin, wing flap skin, tail skin, elevator skin, tail skin, rudder skin and tab , Aileron skins and tabs, slat skin, elevator tabs. Alloy 2524 was born in 1995 and was registered with the Aluminum Association of America in the same year. Its "grandfather" 2024 alloy was born in 1934. Alloy 2524 is the sixth generation of the 2024 alloy family. Their contents are approximately equal in terms of principal components (Cu, Mg, Mn). For example, Alloy 2024 contains 3.8%-4.9% Cu, and Alloy 2524 is 4.0%-4.5%. The Cu;2024 alloy has a magnesium content of 1.2%-1.8%, while the 2524 alloy contains 1.2%-1.6% Mg; the 2024 alloy contains 0.30%-0.9% Mn, while the 2524 alloy contains 0.45%-0.7% Mn, it can be seen that the content of main alloy elements of 2024 alloy is looser than that of 2524 alloy, so the production of 2524 alloy is slightly more difficult.

However, the impurity content of the 2524 alloy is much less than that of the 2024 alloy, which is a very clean alloy. Its impurities Si, Fe, and Cr contents are 0.06%, 0.12%, and 0.05%, respectively, which is only 12% of the 2024 alloy, respectively. %, 50%, and other impurities are also significantly reduced, so the number of impurity phases is much smaller. The conventional mechanical properties of the alloy are comparable to that of the 2024 alloy, but its fracture toughness and stress corrosion cracking resistance, fatigue crack propagation resistance The ability is stronger than that of the 2024 alloy and it is also more tolerant to damage tolerance, so its overall performance is better than that of the 2024 alloy. It is really a generation better than a generation. Parts made from it are more durable, longer maintenance periods, lower maintenance costs, and higher aircraft safety.

T3 indicates that the sheet is stretched after solution treatment, and then sent to the user after aging treatment (natural aging). The user uses the part for processing, because stretching is performed before the user processes the part, so it is called pre-stretching and stretching. The long deformation is 1.5% - 3%. The quenched plates have enormous internal stress. The surface is compressive and the internal is tensile. If they are not eliminated, the user will deform and become waste while processing the part. Pre-tensioning is to eliminate the quenching residual stress. , To facilitate the smooth progress of machining workpieces. The pre-stretched aluminum alloy sheet is called a pre-stretched sheet and is mostly used for the manufacture of aircraft skins. It is a class of high-tech products. Pre-stretching is carried out on a drawing machine. China's current pre-stretching plates include Northeast Light Alloy Co., Ltd., Southwest Aluminum (Group) Co., Ltd., Nanshan Light Alloy Co., Ltd., and Aili International (Zhenjiang) Co., Ltd. Wait for seven.

The ARJ21 aircraft parts made of 2024 type alloy also include: wing underwall processed with 2524-3511 alloy and wing spar web processed with 2324-T39 alloy. The lower edge of the wing spar manufactured with the 2026-T3511 alloy, 2026 alloy is an American Al-Cu-Mg alloy registered in the American Aluminum Association in 1999, and its Cu, Mg, and Mn contents are lower than that of the 2524 alloy. Some, but the difference is not too big, the big difference is that it contains 0.05% - 0.25% Zr and impurities Si, Fe, Cr, Zn, Ti content is lower than the 2524 alloy, so its overall performance than 2524 alloy The superior ones, T3511 shows that after the solution treatment after stretching the extruded material, the tensile deformation of 1% - 3%.

7xxx alloy

In the manufacture of ARJ21 regional passenger aircraft structure, 2524 alloy of 2xxx series is used more often, accounting for about 60% of the total amount of aluminum alloys; followed by 7xxx series alloys accounting for about 35%, mainly using three kinds of alloys: 7050, 7150,7055, these three 7xxx aluminum alloys hold up half of the ARJ21 passenger aircraft, in fact, it can be said that the two alloys, because 7050 alloy and 7150 alloy main components are the same.

7050 alloy is a kind of high-purity super-hard aluminum, not only the content of impurities Fe, Si is low, but also the content of Mn is also very low. The brittle inclusion phase in the structure is greatly reduced, the zinc-magnesium ratio is increased in the main component, and Zr is used as a grain refiner in place of Zr. Due to the improvement of these components and artificial aging treatment, the 7050 alloy has excellent comprehensive properties such as high fracture strength, high fatigue strength, good tolerance to damage tolerance, and good stress corrosion resistance, etc., while maintaining a higher strength. Another outstanding advantage is the high hardenability, especially suitable for the manufacture of thick plates and forgings, thick section parts. The main bearing structures that require high strength, high stress corrosion, exfoliation corrosion resistance and good fracture toughness, such as fuselage frames, bulkheads, wing panels, wing dyes, ribs, landing gear, are mainly used in aircraft. Support parts and rivets. The strength of the 7050 alloy decreases at elevated temperatures, and the long-term use temperature must not exceed 125°C.

The components of the 7050 alloy T7452 used in the ARJ21 passenger aircraft include rear fuselage frames, fuselage frames, fuselage frames above the fuselage wings, and passenger observation window frames.

The 7150 alloy is the development of the 7050 alloy. The Zn content is higher, the Mg content is slightly changed, the Zn/Mg ratio is increased, the Cu content is slightly decreased, and the performance is further improved. The structure made of its T77 state material is The strengths are: wing ribs, ribs, fins, flaps, flaps, flaps, webs, stern flanges, tail webs, webs, sterns Ribs, elevator ribs and beams, flat tail ribs, girth and beam edge heads, rudder ribs, girder and beam edge heads, aileron ribs and beams, ribbed ribs and beams, leading edge ribs, fuselage floor girders Press nips. The load-bearing structural parts made of T7751 state materials are: purlins on the upper and lower wings of the wing, the upper edge of the wing, the long tail, the long part of the fuselage that interfaces with the wing, the body sill, and the underfloor beam. Pressure zone.

Although there are not many parts made of 7055 alloy, they are all stressful and critical. For example, the upper wall of the wing is made of 7055-T77511 alloy, and the landing gear joint is forged with 7055-T77 alloy. Among 7xxx series alloys, 7055 alloy is one of the higher average total alloying elements, which is 12.35%, and the average total iron and silicon content is lower, only 0.125%, so the casting of large slabs is difficult and cold. Cracks tend to be large, and some large slab ingots have so far been impossible to cast economically.

There are nearly 400,000 rivets, and one can't be less

Since the advent of the aircraft for more than 120 years, the riveting of components has been an indispensable joining process. This is still the case. The amount of rivets for each large-scale strategic transport aircraft and the A380 extra passenger aircraft is millions. In a very long period of time in the future, riveting will still be the main process for the connection of components. However, as time goes by, design improvements and advances in welding technology, the riveting workload will be reduced, but the reduction will be slow. For example, an aircraft with a size comparable to that of the ARJ21 passenger plane used about 600,000 rivets per frame three or four decades ago, but it still has to use more than 400,000.

The rivet alloys for ARJ21 regional passenger aircraft include 2014, 2219, 3003, 5052, 5056, and 7050 alloys. The 2219 alloy rivets are used to rivet high-strength internal and external structures. The 7050-T73 alloy rivets are used to rivet high-strength, corrosion-resistant structures. Rivets are subjected to anodizing treatment with sulfuric acid solution and dichromate sealing before riveting.

Cast aluminum alloy

Some cast aluminum alloys were also used in the manufacture of ARJ21 regional passenger aircraft. Although the amount of cast aluminum alloys is much less than that of deformed aluminum alloys, it is also indispensable. For example, 356 and A356 alloy castings are complex in shape, thin in wall thickness, and require airtightness. The moderately loaded structural parts, instrumentation accessories, engine parts, and fuel pump housings are aluminum-silicon-magnesium alloys, equivalent to China's ZL101, which contain 6.5%-7.5% Si, 0.25 % - 0.45% Mg; A356 alloy is a modified type of 356, but its low impurity content and the addition of a small amount of grain refinement elements, thus having a higher mechanical properties.

Cast aluminum alloys for the ARJ21 passenger aircraft also include 413.0, 360, 355, A357, Tens-50, 380, and A380 alloys.

ARJ21 regional passenger aircraft aluminum

All localization soon

The ARJ21 Regional Airliner is the first medium-sized passenger aircraft independently designed and manufactured by China with its own independent intellectual property rights. Regional airliners are aircraft with less than 100 seats. According to the plan of the Shanghai Aircraft Manufacturing Plant, five deliveries were completed at the end of 2016, including two 90-seat and three-seat 78-seat classes. It is expected that 30 deliveries will be completed in the next five to six years, and 880 deliveries will be completed by 2035. The target is 50 aircraft/year and the first phase of the construction target is 30 aircraft/year. According to the plan, aluminum used can reach 100% localization after 2020. The author believes that the establishment of an upstream and downstream cooperation mechanism for civil aircraft aluminum under the leadership of the Ministry of Industry and Information Technology will greatly promote the localization rate of aluminum required for ARJ21 aircraft.

In China, about 20 companies, including Northeast Light Alloy Co., Ltd., Southwest Aluminum (Group) Co., Ltd, and Chinalco Northwest Aluminum Processing Co., Ltd., can produce aluminum alloy plates, foils and foils for ARJ21 passenger aircraft. , tubes, rods and forgings, etc., their equipment is world-class, there is a company from Austrian Ebner (Ebner) company introduced a T77 processing aging furnace, the furnace temperature design temperature ± 1 °C, Furnace gas temperature accuracy ± 2 °C, plate temperature uniformity ± 1.5 °C, single plate temperature uniformity ± 1 °C, can handle plate size (mm): Thickness 4 - 250, width 1000 - 4300, length 2000 - 39,000, the larger board mass 25t. In the aluminum used in the ARJ21 passenger aircraft, it is difficult to produce T77 material. As long as this material can be produced, the bulk supply of all other materials is not a problem, and equipment plays an important role in the production of this material.

The selection of ARJ21 aircraft is mainly made of aluminum alloy. The quality of aluminum components accounts for 75% of the net mass of the aircraft (using an empty weight of 24955kg) 25t of 25t, or about 50t (including castings and forgings), that is, the need to purchase 50t of aluminum; structural steel and 10% of stainless steel; 8% of composites; 2% of titanium alloys; 5% of other materials. Before 2020, if 30 aircraft are produced each year, the larger amount of aluminum used per year is 1500 tons.

It must be emphasized that the properties and indicators of the supplied aluminum materials must fully meet or exceed those imported from Okoninuk Aluminum for the manufacture of prototype forensics machines, in order to completely replace the imported products, at the same time the price is reasonable and there is an international market. Competitiveness.

Exit Sign For Aluminum And Acrylic

The LED exit sign light is specially made from aluminum and acrylic materials, and is also fast dissipating heat, insulating and corrosion resistant. LED emergency lights are illuminated with super bright LEDs to ensure visibility in dark corridors and hallways. In case of an emergency power outage, the exit lane will be illuminated. Exit signs are designed for various types of indoor commercial uses such as hotels, shopping centers, theaters, restaurants and other public places. Any emergency exit signs must have continued reliability. Easy to install and can be hung on the wall or from the ceiling.

Emergency Light Sign,Wall Mounted Exit Sign,Led Emergency Exit Sign,Battery Operated Exit Signs

Jiangmen City Pengjiang District Qihui Lighting Electrical Appliances Co., Ltd , https://www.qihuilights.com