Alum 5083 and 5086 for Shipbuilding
Alum 5083 has high strength, good weldability, and strong corrosion resistance. It is one of the important materials for shipbuilding. However, because 5083 aluminum plate is used in the ocean, atmosphere, water and other environments all the year round, will inevitably be corroded.
One of the more common forms of corrosion is intergranular corrosion. The solid solution of Mg atoms in the aluminum matrix can significantly improve the strength of the aluminum alloy, but when the mass fraction of Mg in the aluminum alloy exceeds 3.5%, after a period of use at a temperature of 50-200 °C, aluminum alloys are prone to intergranular corrosion and stress corrosion.
The self-corrosion potential of 5083 aluminum alloy fluctuates violently at the initial stage of immersion, showing a trend of first decreasing and then increasing, which is consistent with the change law of corrosion potential of high-entropy alloys.
After 10 h, the self-corrosion potential gradually stabilized around -760 mV, with little fluctuation. After that, the surface state of the 5083 aluminum alloy is basically stable, and the corrosion reached a stable stage. The self-corrosion potential of 5083 aluminum alloy in the stable corrosion stage is much higher than that of general aluminum alloy materials, and the higher self-corrosion potential reflects the good corrosion resistance of 5083 aluminum alloy in seawater.
Ships are subjected to cold processing (such as hemming, crimping, roll bending, stamping, etc.) and thermal processing (such as hot bending, pyrotechnic orthopedics, etc.) during the construction process. Therefore, the marine aluminum alloys are required to be easy to process and form. There are no defects such as cracks during processing, and the performance requirements such as strength and corrosion resistance can still be met after processing. The 5083 aluminum plate meets the performance requirements of marine aluminum plates.
5086 h32 aluminum plate is another important marine aluminum sheet. Its magnesium content generally does not exceed 7%. With the increase of the magnesium content, the strength of the alloy will increase, and the plasticity will decrease.
5086 anti-rust aluminum sheet is usually used in the annealed state, cold hardened or semi-cold hardened state. Due to the effect of magnesium, the density of 5086 aluminum sheet is higher than that of other aluminum plates, and it has good corrosion resistance.
Generally speaking, the state of commonly used 5086 marine aluminum plate is O, H111, H112, H116, H321, etc. In terms of mechanical properties, the tensile strength of 5086 aluminum sheet is≥240, conditional yield strength is ≥95, elongation is ≥10 and elongation is ≥12.
