Magnetic Pulse Welding (MPW) is a joining technique favorable for the generation ofstrong atomic bonded areas between different metals, e.g. aluminum and steel. Brittleintermetallic phases can be avoided due to the high-speed collision and the absence ofexternal heat. The demand for the use of this technique in industries like automotive andplant engineering rises. However, workpieces used in these fields are often coated, e.g. inorder to improve the corrosion resistance. Since the weld quality depends on the material’sbehavior at the collision zone, surface layers in that region have to be taken into accountas well.This work investigates the influences of different coating types. Aluminum to steelwelding is used as an example system. On the inner steel part (C45) coatings like zinc,nickel and chrome are applied, while the aluminum flyer tubes (EN AW-6060) areanodized, chromated and passivated. Welding tests are performed using two differentwelding systems with varying discharging frequencies and four geometrical part setups.For all combinations, the flyer velocity during the process is measured by Photon DopplerVelocimetry (PDV). By using the uncoated material combination as a reference, theremoval of surface layers due to jetting is analyzed. Finally, the weld quality ischaracterized in peel tests, shear-push tests and by the help of metallographic analysis. Itis found that certain coatings improve the joint formation, while others are obstructive forthe performance of MPW. Some coatings have no influence on the joining process at all.
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