Ship aluminum alloy is one of the emerging fields of aluminum alloy products, and it is also the key direction of transformation and upgrading of many domestic aluminum processing enterprises. Ship aluminum alloy is used in marine ships and other fields, so it has stricter process requirements and performance standards than other ordinary aluminum alloy products.
Selection principle of ship aluminum alloy
The selection principle of ship aluminum alloy materials can be divided into four aspects. First, it has high specific strength and specific modulus. The structural strength and size of ships are closely related to the yield strength and elastic modulus of the material. Since the elastic modulus and density of aluminum alloys are roughly the same, the addition of alloying elements has little effect. Therefore, increasing the yield strength within a certain range is effective in reducing the structure of the ship. It is usually difficult for high-strength aluminum alloys to have excellent corrosion resistance and weldability at the same time. Therefore, marine aluminum alloys are generally medium-strength, corrosion-resistant, and weldable alloys.
The second is an excellent welding performance. At present, the automatic argon arc welding method is mainly used in ships. Good weldability means that the tendency of aluminum alloys to form during welding is smaller, which means that aluminum alloys must have good welding crack resistance. Because under shipbuilding conditions, the lost welding performance cannot be restored by heat treatment again.
The third is excellent corrosion resistance. Ship structures are used in harsh seawater media and marine environments. Therefore, corrosion resistance is one of the main signs of marine alloys.
The fourth is that aluminum alloy has a good cold and hot forming properties. Because shipbuilding requires multiple treatments such as cold processing and hot processing, marine aluminum alloys must be easily processed and formed without cracks, and they can still meet the strength and strength after processing. Corrosion resistance requirements.
Ship aluminum alloy materials are more stringent. Currently, aluminum alloy products such as 5083, 5086, 5454, 5754, and 6061 are mostly used. In practical applications, the advantages of marine aluminum alloys are very obvious. The first is the small specific gravity, which can reduce the weight of the ship, save energy, and increase the load. Secondly, it has good corrosion resistance, reduces the cost of oiling, and extends the service life. The third is the welding and processing formability number, which is conducive to later processing. The later aluminum scrap is easy to recycle and can be recycled. At the same time, it does not burn and is safe in a fire.