Resistance Spot Welding of Galvanized HSLA Steels

摘要

HSLA galvanised steels of two different thickness 1.80 mm and 3.09 mm were characterized as well as their zinc coatings, chemical composition and metallography analysis were obtained, also simple tensile mechanical testing and microhardness were measured, the coatings thickness and roughness were also obtained. Afterwards the welding parameters were obtained in order to fulfill the minimum welding bottom, varying the welding current and the holding time. On the welded strips peel tests were carried out and microhardness obtained along the welded bottom, the final diameter of welded bottoms was measured. Once the parameters were obtained the quality test took place on coups and characterized each 25 welded spots, up to 1000 welded spots on each steel, metallography of the cross section of the welded bottoms and microhardness were carried out, also mechanical tensile testing, at the end of the welding campaign the wear of the electrodes was measured.