Marine aluminum alloy is one of the emerging fields of aluminum alloy products, and it is also the key direction of domestic aluminum processing enterprises transformation and upgrading. Marine aluminum alloy is used in marine and other fields, so it has more stringent process requirements and performance standards than other common aluminum alloy products.  
The principle of material selection for marine aluminum alloy can be divided into four aspects. There is a high ratio of strength and modulus, yield strength and elastic modulus of the ship structure strength and size and material is closely related to the elastic modulus and density of Aluminum Alloy is largely the same, adding alloy elements also have little effect, so in a certain range to improve the yield strength of ship structure effectively reduce. High strength aluminum alloys are often difficult to have excellent corrosion resistance and weldability at the same time. Therefore, marine aluminum alloys are generally of medium strength and corrosion resistant weldable alloys. Two is excellent welding performance. At present, the automatic argon arc welding method is mainly used in ships, and good weldability means that the tendency of cracks in welding of aluminum alloy is small, that is to say, aluminum alloy should have good welding crack resistance. Because of the shipbuilding condition, the lost welding performance can not be resumed by RE heat treatment. Three is the excellent corrosion resistance, the ship structure in harsh seawater medium and the use of the marine environment, therefore, corrosion resistance is one of the main signs of marine alloy. The four is Aluminum Alloy has good cold and hot forming performance, because the manufacture of ships to the cold and hot processing of various processing, so marine Aluminum Alloy must be easy to process, does not produce cracks, and after processing can still meet the requirements of strength and corrosion resistance.  
The selection of marine aluminum alloy is relatively strict. At present, the aluminum alloy products such as 5083, 5086, 5454, 5754 and 6061 are widely used. In practical application, the advantage of marine aluminum alloy is very obvious. First of all, the weight is small, it can reduce the ship weight, save energy consumption, increase the carrying capacity; The second is good corrosion resistance, reduce oil and other expenses, extend the service life; Three is welding, processing formability number, conducive to later processing; finally, aluminum scrap is easy to recycle, can be recycled, at the same time, not burning, fire safety.