一、前言目前,登陆艇、快艇、猎潜艇、气垫船水翼艇和旅游艇的艇体用材以及军舰、航空母舰的上层建筑结构,出于其速度、机动性和稳定性的考虑,越来越多地使用了变形铝合金,而且倾向于选择Al-Mg系变形铝合金作为舰、船用材,因为Al-Mg系合金一般有合适的强度和良好的可焊性、耐蚀性、成型性。但现在,舰、船用Al-Mg系合金中的Mg含量,基本上都控制在5％(重量 I. Introduction At present, superstructure structures of landing craft, speedboats, hunting submarines, hovercraft and pleasure craft, as well as superstructures of warships and aircraft carriers, are increasingly being considered for their speed, mobility and stability The use of deformed aluminum alloy, but also tend to choose Al-Mg-based deformation of aluminum alloy as a ship, ship timber, because Al-Mg alloys generally have the appropriate strength and good weldability, corrosion resistance, formability. However, the contents of Mg in ships and marine Al-Mg-based alloys are basically controlled at 5% by weight