补焊对7N01焊接接头腐蚀行为的影响

Effect of repair welding on the corrosion behavior of 7N01 aluminum alloy welded joint

摘要:

实际生产过程中，补焊过程往往焊接接头的可靠性产生影响。本文研究了补焊对7N01-T5/7N01-T4异种铝合金腐蚀性能的影响。结果表明，补焊会导致焊接接头耐蚀性降低，特别是热影响区域。焊接接头腐蚀性能演变主要与补焊过程中Zn元素从基体向晶界处的扩散有关。

Abstract:

Mandatory repair welding for production of structural parts easily causes problems to the reliability of welded joints due to the resultant extra thermal cycle. The evolution of corrosion resistance of repair welded joint between 7N01 aluminum alloy in T5 and T4 state by metal inert gas welding process was investigated. The results reveal that repair welding deteriorated the corrosion resistance of weldment, especially of the heat-affected zone. The main reason for the change in corrosion resistance of repair weldment could be related to the transformation of precipitates and diffusion of Zn from the matrix to grain boundaries caused by the extra thermal cycles.