TY  - JOUR
A1  - Akyel, Fatma
A1  - Üstündag, Ömer
A1  - Bakir, Nasim
A1  - Brunner-Schwer, Christian
A1  - Gumenyuk, Andrey
A1  - Rethmeier, Michael
T1  - Influence of heat input on cooling rates and mechanical properties of laser hybrid welded thick structural steels
JF  - Welding in the World
N2  - Laser hybrid welding presents several challenges when used to weld thick steels. A typical weld is divided into the arcdominated and laser-dominated zone. These zones lead to variations in the mechanical properties of the weld. The laserdominated zone is of particular importance regarding mechanical properties, notably Charpy impact toughness, due to the high cooling rates and the absence of filler wire. The low heat input of the laser can lead to martensitic microstructure causing hardening and deterioration of impact toughness. The high heat input of the arc can lead to grain coarsening and even loss of impact toughness. This study examines the influence of heat input on the cooling rates, microstructure and mechanical properties of single-pass laser hybrid welded steels of S355J2 and EH36 with thicknesses up to 30 mm. The experiments were performed with a 20-kW fibre laser and a contactless electromagnetic weld backing in the butt-joint configuration in 1G welding position. The cooling time was measured in three different locations near the fusion lines corresponding to different heights of the seam using a special configuration with pyrometers, collimators and optical fibres. The test specimens for the Charpy impact testing and tensile testing were extracted in three different depths. The experiments indicated that a heat input of 1.6 kJ/mm–2 kJ/mm, 2 kJ/mm–2.4 kJ/mm and 3.7 kJ/mm were recommended when single-pass laser hybrid welding of 20-, 25-, and 30-mm-thick structural steels regarding the minimum requirements of the mechanical properties, respectively.
KW  - Laser hybrid welding
KW  - Heat input
KW  - Mechanical properties
KW  - Charpy impact toughness
KW  - Cooling rate
PY  - 2025
UR  - https://nbn-resolving.org/urn:nbn:de:kobv:b43-625282
DO  - https://doi.org/10.1007/s40194-025-01924-8
SN  - 1878-6669
SP  - 1
EP  - 15
PB  - Springer
CY  - United Kingdom
AN  - OPUS4-62528
LA  - eng
AD  - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER  -