The characteristics of 7175 T74 forged aluminum plate is to maintain the content of 7075 alloy main elements and reduce the content of alloy iron and silicon impurity content, and adopt special T and heat treatment process to make the alloy strength close to 7075-T6 alloy.
Stress resistance, corrosion performance is close to the best corrosion resistance state 7075 T73, its fatigue performance is similar to 7075 T6 alloy.
The reduction of Fe and Si impurities can not only replace the forging performance of the alloy, but also significantly improve the stress resistance, corrosion resistance and fracture toughness.
Especially 7175 T74 forged aluminum plate as a forged alloy improves the low plasticity and fracture toughness of 7075 alloy in the short transverse direction, which is more important for forged structural parts with three-way load. This shows that 7175-T74 alloy replaces 7075 -T6, T73 alloy in a special field is an inevitable result of the development of materials science, and is an urgent need of China's aerospace industry.
The production introduction of 7175 T74 forged aluminum plate:
Intermediate thermomechanical treatment is to use the combination of homogenization, hot processing and high temperature recrystallization to achieve the purpose of fully solidifying the alloy elements. Furthermore, the crystal morphology is controlled by crystallization inhibitors and large deformation, reducing the size of the crystal grains and reducing the degree of grain fibrosis, making it difficult for the grain boundaries of the recrystallized fine grains to move to ensure the mechanical properties. Finally supplemented with a two-stage aging similar to T73
(Over-aging) Ensure that the material has good resistance to stress corrosion.
The low iron and silicon impurity content in 7175 alloy is particularly important for improving fracture toughness, especially in the short transverse direction.
A large number of research results on the analysis of the chemical elements and components of 7075 alloy show that on the basis of keeping the content of the main components of 7075 unchanged, by reasonably controlling the content of Cr and Ti and reducing the content of Fe and Si impurities, the 7175 alloy developed Gold will have better comprehensive mechanical properties.
In particular, the transverse mechanical properties and fracture toughness of alloy forgings have been greatly improved. It is a promising high-strength structural aluminum alloy. 7175 T74 forged aluminum plate is currently the best high-strength aluminum alloy forging for industrial production.