Aluminum alloy is the most widely used in industry of non-ferrous metal structural materials, in aviation, aerospace, automotive, machinery manufacturing, shipping and have been extensively applied in chemical industry. The rapid development of industrial economy, the demand for aluminum alloy welding structure is increasing, also make the weldability of aluminum alloy and research.
Aluminium alloy is usually use copper, zinc, manganese, silicon, magnesium alloy elements, such as the beginning of the 20th century by the German Alfred Wilm invention, help greatly to aircraft development, a large post-war German aluminum alloy components are classified as state secrets. Have a lighter compared to the ordinary carbon steel and corrosion resistant performance, corrosion resistance than pure aluminium. The surface of the aluminum alloy in a clean, dry environment can form the oxide layer of protection.
Caused by galvanic corrosion accelerating things are: aluminum alloy and stainless steel contact situation, other metal corrosion potential is lower than aluminum alloy or in damp environment. If the aluminum and stainless steel to be used together must have water - containing systems or electronic or electrolytic separation between two metal outdoor installation.
Aluminum alloy components to the Aluminium Association, AA registration. Many organizations publish more detailed manufacturing aluminum alloy standard, including the Society of Automotive Engineers, SAE especially aviation standards, and American Society for Testing and Materials, ASTM.
Aluminum alloy is the most widely used in industry of non-ferrous metal structural materials, in aviation, aerospace, automotive, machinery manufacturing, Marine aluminium alloy and have been extensively applied in chemical industry.
As the science and technology in recent years, as well as the rapid development of industrial economy, the demand for aluminum alloy welding structure is increasing, also make the weldability of aluminum alloy and research. Aluminum alloy is widely used to promote the development of aluminum alloy welding technology, at the same time, the development of welding technology and expand the application field of aluminum alloy, thus the welding technology of aluminum alloy is becoming one of the hot spot of research.
The density of pure aluminum (rho = 2.7 g/cm3), is about 1/3 of the iron, low melting point (660 ℃), aluminum is face-centered cubic structure, therefore, has the very high plasticity (delta: 32 ~ 40%, and bits of: 70 ~ 90%), easy to machining, can be made into various molding, plate. Corrosion resistant performance is good; But the strength of pure aluminium is very low, annealing state sigma b value is about 8 KGF/was, therefore, not as a structural material. Through the long-term production practice and scientific experiment, people gradually to add alloy elements and using the method of heat treatment to strengthen aluminum, it's got a series of aluminum alloy.
Add some elements to form the alloy while maintaining the advantages of pure aluminum light can also has high strength, sigma b value can reach 24 ~ 60 KGF/was respectively. So that its "strength" (the ratio of intensity and the proportion of sigma b/rho) is better than a lot of alloy steel, become the ideal structural material, widely used in machinery manufacturing, transportation, machinery and aviation industry, the aircraft fuselage, skin, such as compressor with aluminum alloy manufacture, in order to reduce weight. The welding of aluminum alloy instead of steel material, the structure can reduce more than 50% in weight.