The study of high-performance corrosion resistance materials is the most fundamental factor for enhancing the performance of ship equipment. Aluminum alloy is an important material in the process of ship construction，and its overall performance has a significant impact on the combat performance and service stability of weapon equipment. Semiconductor and electrochemical properties of passivation film of a new Al-2.6Mg-1.7Si-X alloy with high strength and anti-corrosion in the marine environment are effectively analyzed by means of the first principles and electrochemical methods. The results show that the formation of stable continuous protective film of Al-2.6Mg-1.7Si-X alloy in sea water can effective improve the corrosion resistance by inhibiting the migration of electrons and vacancy from semiconductor film to solution. The electronic contributions of Mg3p and O2s are the main factors affecting the corrosion current. This result can provide a basis for the development and replacement of related materials.
