Dataset on cooling time (t8/5) and thermal cycle measurements during electron beam welding of quenched and tempered high strength structural steels

In this paper, the dataset presents experimentally measured thermal cycles and cooling times (t_8/5) derived during electron beam welded (EBW) of high strength structural steels (HSSSs) in quenched and tempered (<i>Q</i> + <i>T</i>) condition with strength grades ranging from 690 MPa -1300 MPa. The dataset can support the calibration of thermomechanical models, training of AI models for HAZ prediction, and optimization of EBW parameters. These steels are widely used for lightweight structural applications that require high strength, toughness and reliability. The data were recorded for normal EBW and EBW with beam oscillation using K-type thermocouples positioned at 1.55 mm and 2 mm from the weld centerline. The experiments were performed under high vacuum chambers of EBW machine using precisely controlled process parameters. The cooling times were evaluated in the critical 800 -500 °C temperature range (t_8/5) as a function of linear energy and welding parameters. The dataset also includes optical micrographs of the base materials (BM), fusion zones (FZ) and different subzones of the heat-affected zones (HAZ) under various welding conditions. This dataset provides detailed information bridging EBW process variables, plate thickness etc. to measure cooling times in multiphase HSSSs. It provides crucial experimental results for understanding thermal behavior in EB-welded joints which are extremely useful for structural components with sophisticated joint structures. The open access dataset can be reused in various research and development studies like thermo-mechanical modelling, heat-affected zone (HAZ) simulations, and residual stress analyses. It will also support future research focused on improving joint strength, reducing cold cracking susceptibility to maintain structural reliability, and promoting cost-effectiveness in diverse engineering applications.