TY - JOUR T1 - Microstructure and mechanical properties of similar and dissimilar laser welds of dp600 and dp1000 steel sheets used in the automotive industry AU - Tunçel, Oğuz AU - Aydın, Hakan AU - Çetin, Şükriye PY - 2021 DA - January DO - 10.31127/tuje.649975 JF - Turkish Journal of Engineering JO - TUJE PB - Murat YAKAR WT - DergiPark SN - 2587-1366 SP - 8 EP - 14 VL - 5 IS - 1 LA - en AB - Dual-phase (DP) steel sheets are the most widely used steel group in the automotive industry. When these steel sheets are used in car body components, welding is inevitably needed during the manufacturing process. Although the resistance spot welding (RSW) is the most widely used welding method in the automotive industry, the newly popular laser welding has gained more importance in the welding of these steel grades in recent years. In this work, the DP600 and DP1000 steel sheets were joined as double-sided with the pulsed Nd: YAG (Neodymium-doped Yttrium Aluminum Garnet (Y3Al5O12)) laser welding. Performing similar or dissimilar weld of DP steel sheets is an inevitable demand in the modern automotive industry. So, in this study similar (DP600-DP600, DP1000-DP1000) and dissimilar (DP600-DP1000) steel sheets were welded in the flat position with the butt joint. In order to evaluate welding performance, microstructural studies and mechanical tests were performed, and experiments carried out in this context include optical microscope studies, tensile tests and Vickers microhardness measurements. The tensile strength of the similar welded joints is a little bit lower than the base metals (BM). But, for dissimilar weld, the tensile strength is even lower than DP600-DP600 joint. 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