Aluminum alloy, which has many characteristics such as low density, high strength, good toughness and corrosion resistance, is an indispensable and important structural material in aerospace, transportation, machinery manufacturing and even military and defense construction. The "ultra-high-strength aluminum alloy" with excellent comprehensive properties has become one of the key new materials developed by various countries.
Recently, China has achieved breakthroughs in the development of aluminum alloy materials, and successfully developed the current "world's highest tensile strength" aluminum alloy metal material-ultra-high strength aluminum alloy. The tensile strength of ultra-high-strength aluminum alloy reaches 950 MPa. In addition, the maximum yield strength of ultra-high-strength aluminum alloy is also world-class, reaching 874-895 MPa. Both indicators can win the world crown.
This technology was developed by China SX Light Alloy Material Technology Group after more than 10 years of research and development, and has obtained 37 invention patents in the field of "ultra-high strength aluminum alloy".
High-strength aluminum alloy refers to the aluminum alloy whose tensile strength is greater than 480MPa, mainly based on Al-Cu-Mg and Al-Zn-Mg-Cu alloys, namely 2XXX (hard aluminum alloy) and 7XXX (super hard Aluminum alloy) series alloy. The static strength of the former is slightly lower than the latter, but the use temperature is higher than the latter. Due to the differences in alloy chemical composition, smelting and solidification methods, processing techniques and heat treatment systems, the properties of alloys vary greatly.
At present, the highest strength of 7090 aluminum alloy in North America is 855 MPa, and the strength of European aluminum alloy is 840 MPa. Japan ranks first at 900 MPa. However, the maximum tensile strength of China’s ultra-high-strength aluminum alloy can reach 917-957 MPa. The yield strength can reach 874-895 MPa!
The ultra-high-strength aluminum alloy invented this time adopts brand-new technology, and the product has the characteristics of wear-resistant rigidity and high strength, which is at the international leading level. The ultra-high-strength aluminum alloy is a high-performance, ultra-super wear-resistant and ultra-high-strength product produced by a new technology. Its relative density can reach more than 99.6%. After subsequent hot processing (forging, rolling, extrusion or hot pressing), it can also be formed Dense product.
After the ultra-high-strength aluminum alloy is treated with T6 technology, its thermal conductivity is approximately equal to 171W/mK; the linear expansion coefficient is approximately equal to 23.5um/(mK); the elongation is A%3.5, the hardness HRB≥98, and the compressive strength is greater than 80 MPa. The indicators are all international leaders.
The abstract of the patent description of ultra-high-strength aluminum alloy by the State Patent Office of China stated: “The present invention provides an ultra-high-strength aluminum alloy and a preparation method thereof. The aluminum alloy material is prepared with a specific formula. Its microstructure is obvious. Refined, the precipitated phase is fine and uniformly distributed, so that its mechanical properties have almost no anisotropy, and it has the advantages of high strength, high toughness, high stiffness, and light weight. The experimental results show that the ultra-high-strength aluminum alloy provided by the present invention is T6 After treatment, its tensile strength ≥917MPa, and yield strength ≥874MPa".
Compared with the traditional process, this technology ensures the uniform and fine distribution of the alloy, no segregation phenomenon, high precision, uniform structure, excellent performance, low comprehensive production cost, etc., and has high corrosion resistance. It is resistant to high salt and high acid. , High alkali has good anti-corrosion effect, especially the unique anti-corrosion to seawater. The product is still bright as new after three years of experiment immersion in various sea areas in China, there is no parasitic phenomenon of marine organisms, and no pollution to the environment. The human body is harmless.
The significance of this invention of ultra-high-strength aluminum alloys lies not only in the optimization of aluminum alloy properties and the international leadership of various indicators, but also in its wide range of applications and manufacturing prospects.
However, it is reported that the ultra-high-strength aluminum alloy developed by China has high corrosion resistance, especially for seawater with unique corrosion resistance. Related test results show that products made from it are still as bright as new after being immersed in various marine water environments in China for 3 years. They are simply the best choice for high-performance ship building materials. However, the role of ultra-high-strength aluminum alloy is more than that. It can also be used to make armored bulletproof materials, track shoes, bullet casings and many other weapons and equipment. Therefore, it can be foreseen that the popular trial of ultra-high-strength aluminum alloys will push China's metal manufacturing industry to break through tradition and enter the forefront of the world.
Relevant experts believe that the invention and application of ultra-high-strength aluminum alloys have completely solved the material problem for the manufacture of oil and gas pipelines and ultra-high pressure vessels, making China a world leader in the field of ultra-high pressure vessel manufacturing.
Products made of ultra-high-strength aluminum alloys can be widely used in aerospace and navigation, ordnance industry, petroleum pipeline transportation, urban water pipeline networks, electronic information engineering, modern buildings, traffic bridges, medical equipment, auto parts, construction machinery, etc. Sharp field. In particular, the product has a melting point of only 780 degrees Celsius, which is very suitable for 3D printing materials.
It is expected that in the near future, the popularization and application of ultra-high-strength aluminum alloys will enable China's metal manufacturing industry to greatly break through the traditional scope and take the lead in the world.