The Effect of Corrosion on The Mechanical Behavior of The Dissimilar Material Joints (Aluminum – Steel) Using The Friction Stir Spot Welding Method

Abstract

Multi-material design is a viable approach to reduce fuel consumption as well as environmentally gas emissions in automotive industry by reducing weight. However, joining aluminum to steel is challenging because galvanic and crevice corrosion may occur when two dissimilar metals are in contact with one another in the presence of an electrolyte. In this paper, corrosion behaviors of the friction stir spot welded aluminum steel joints were investigated to understand how mechanical properties change after salt spray test at 150 – 300 – 500 hour and visual controls have done to support the mechanical property results. It is found that, e-coat treatment has a strong effect on corrosion prevention. Due to the fact that the car body sheet metals have e-coat application, the aluminum-steel coupled body plates will not have any negative effect on corrosion and it has been determined that they can be used in the mass production without the need for any intermediate insulator materials.