Electrospark deposition interlayers for dissimilar resistance welding of steel to aluminum

The transportation industry is facing increasing pressure to lightweight vehicles and improve fuel economy. One option is the use of low-density aluminum alloys rather than steels. However, adoption of aluminum alloys is hampered by challenges during the welding of aluminum to steel. Here, an electrospark deposition AA4043 interlayer is applied for the dissimilar resistance spot welding of an aluminum alloy (AA5052) to a galvanized dual phase steel (GI DP600). A minimum 30% tensile lap-shear strength increase is obtained using this interlayer. This manufacturing technique has the potential to allow for greater adoption of aluminum alloys in vehicle lightweighting applications.