EnglishViews: 202 Author: Julong Publish Time: 2023-06-26 Origin: aluminum panel systems manufacturer
Aerospace aluminum is a type of ultra-high strength deformed aluminum alloy that is increasingly being employed in the aviation sector. Aluminum alloy for aviation has higher standards for strength, hardness, toughness, fatigue resistance, and plasticity than regular aluminum alloy. The aerospace plate has improved mechanical and processing qualities, good plasticity after solution treatment, strong heat treatment strengthening effect, and high strength and toughness, making it a perfect material for aircraft construction.
Aerospace aluminum alloys have the following characteristics: large-scale and monolithic, thin-walled and lightweight, precision of section size and shape tolerance, uniformity, and quality of organization and performance. Aerospace aluminum alloys are classified as high-strength aluminum alloys, heat-resistant aluminum alloys, and corrosion-resistant aluminum alloys based on the conditions and parts of the aircraft. High-strength aluminum alloys are increasingly commonly employed in aircraft fuselage sections, engine compartments, seats, maneuvering systems, and so on.
Another feature is that it is difficult to weld. Given the welding difficulty of aluminum alloy, therefore, the manufacturing of integral structural parts by heat deformation of aircraft panels will be a major development trend in the future.
Aircraft panel is mainly a deformed aluminum alloy that can be heat treated, such as 2000 and 7000 series aluminum alloy.
2000 series aluminum alloy represents 2024, 2A16 (LY16), 2A02 (LY6). 7000 series aluminum alloy represents 7075 mainly contains zinc element, also belongs to aviation series, it is aluminum-magnesium-zinc-copper alloy, it is heat treatable alloy, belongs to super hard aluminum alloy, has good wear resistance, also has good weldability, but the corrosion resistance is poor. 2024 aircraft panel is used in applications requiring High strength and hardness (including high temperature) occasions, such as aircraft heavy, forgings, thick plate and extrusion materials, wheels and structural components, multi-stage rocket leaning forward fuel tank and spacecraft parts, truck frame, and suspension system parts.
It is reported that the spacecraft into the air, with every 1 kg reduction, its launch costs will save about $ 20,000, so the structure of weight reduction in the field of space can be described as "gram count". If the weight of the fighter aircraft to reduce by 15%, it can shorten the aircraft glide distance by 15%, increase the range by 20%, and improve payload by 30%. Therefore, countries around the world attach great importance to the development and development of aerospace lightweight structural materials.
With the unique advantages of low density, moderate strength, easy processing and forming, strong corrosion resistance, abundant resources, and high recyclability, aerospace panels have received attention from all parties and are widely used in the aerospace field.
At present, the skin, beams, ribs, trusses, spacer frames, and landing gears of aircraft can be made of aluminum alloy, and the crew cabin, front fuselage, middle fuselage, rear fuselage, drogue, flaps, elevating ailerons and horizontal tail of space shuttle can all be made of aluminum alloy. The amount of aluminum used in an aircraft varies depending on the application. For example, the aluminum alloy used in Boeing 767 passenger aircraft accounts for 81% of the weight of the airframe structure.
At present, the aluminum alloy materials applied in aviation civil aircraft mainly include aluminum alloy castings, aluminum alloy forgings, large section aluminum alloy extrusion profiles, aluminum alloy thick plates, aluminum-lithium alloy, etc.
The production requirement for big aircraft in China is heavily pushing demand for aluminum alloy materials, particularly aviation panel materials. The C919 big passenger aircraft has already received over 500 orders from more than 20 airlines both domestic and international, and the ARJ21-700 has received over 200 orders as well. By 2018, more than 30% of aluminum alloy materials used in ARJ21 regional passenger aircraft and C919 big aircraft will be made in the United States, according to the proposal. Furthermore, the rising demand for aluminum alloy materials for China's large aircraft has accelerated the growth of China's aviation panel R&D and scale industry chain.
Instead of the typical splicing structure, the integral component of aluminum alloy refers to a new structure comprised of huge components manufactured from full billets. The two primary types of billet materials for aluminum alloy monolithic structural parts are die-forged parts and pre-drawn plates. Pre-stretched plates have become increasingly popular for aluminum alloy sections of plane-type integral structural parts, plates, frames, ribs, and beams as metal slab manufacturing levels have improved. Pre-stretched plates are used to minimize and homogenize the inherent internal stress condition by pre-deforming the blank material on a particular plate stretching machine with a limited amount of plastic deformation. However, during the whole process, in addition to the influence of the material and structural characteristics of the workpiece, temperature changes, initial residual stresses in the blank and the cutting process can affect the processing of the whole part.
Therefore, in the manufacture of aerospace plate monolithic components, the developed monolithic structural component deformation prediction system is used to complete the prediction of the workpiece's milling processing deformation for a specific blank workpiece and machining process; the main forms and causes of workpiece deformation are analyzed in conjunction with the structural characteristics of the workpiece; a simulation system is used in the machining engineering, and the result data calculated by the simulation system is directly transferred into the optimization module, and by establishing the relevant mathematical model, the existing process parameters are automatically optimized to realize the real-time control of CNC machining and complete the machining of the whole component.
As far as the domestic industry is concerned, most of the enterprises are concentrated in the middle and lower reaches, and only large enterprises such as Aluminum Corporation of China and Nanshan Aluminum are involved in the production of bauxite and alumina in the upstream industry, and there are more listed companies in the production of primary aluminum and aluminum processing.
The process of primary aluminum production needs bauxite ore, a total of 28.3 billion tons worldwide, mainly concentrated in Guinea, Australia, and Brazil, the combined reserves account for 57% of the world, and product distribution is mainly concentrated in Australia, China, and Brazil, the combined production accounts for 61% of the world.
The total amount of bauxite in China is about 735 million tons, concentrated in Shanxi, Guizhou, Henan, and Guangxi 4 provinces (regions), accounting for about 90.9% of the total national reserves. The reserves of the remaining 15 provinces, autonomous regions, and municipalities directly under the central government with bauxite ore together account for only 9.1% of the country's total reserves.
In addition to the concentrated distribution of bauxite ore in China, there are mostly large and medium-sized deposits. There are 31 large deposits with reserves greater than 20 million tons, and their reserves account for 49% of the country's total reserves; there are 83 medium-sized deposits with reserves between 20 million tons and 5 million tons, and their reserves account for 37% of the country's total reserves, and the total number of large and medium-sized deposits accounts for 86%.
In the face of China's bauxite ore self-sufficiency gradually declining, the future of China's bauxite ore dependence on imports is a major trend, Chinese enterprises urgently need to increase internal mining, prospecting efforts, as well as accelerate the pace of overseas mine acquisition, to protect the future supply of raw materials. China's alumina supply gap is not large, the market has tended to saturate, on the premise of a sufficient supply of bauxite, fully able to protect the primary aluminum production needs.
Since 2008, affected by the financial crisis, China's primary aluminum capacity utilization rate declined, thus the slow growth of production. Driven by the national investment demand in 2009, idle production capacity in 2010 resumed production, and production also increased significantly by 24.4%. In recent years, under the background of energy conservation and emission reduction, the country has implemented a policy of limiting electricity and production in the electrolytic aluminum industry, and the growth rate of primary aluminum production has slowed down. The consumption of primary aluminum is affected by the economic environment and national policies, and the growth rate shows the same trend of change as the production, and the growth rate is slowing down.
The downstream industry chain of aircraft panels is mainly the processing and use of aluminum alloy. The aircraft panel is mainly a deformed aluminum alloy that can be heat treated and strengthened. Therefore, the downstream processing of aircraft panels is particularly important.
The downstream application field of aircraft panel processing material is very broad and has a close relationship with industry, transportation, and consumption level improvement. Forgings, rolled plates, and other aluminum profiles are the most common types of aluminum alloy used in aviation. The transportation industry, particularly the construction of airplanes and missiles in the fields of aerospace and national defense, is the primary downstream demand for aviation aluminum.
With the development of China's big aircraft industry and rail transportation sector in recent years, the downstream processing industry of aircraft panels has entered a rapid development stage, and consumption of aviation aluminum profiles in China has remained strong.
