Influence of local thermal conditions on solidification patterns in laser beam welding: An experimentally aided phase-field study

Solidification cracking in laser beam welding (LBW) is governed by local thermal conditions at the weld-pool boundary, yet the sub-micron microstructural response across the full mushy zone remains poorly understood. This study employs an automated phase-field (PF) simulation workflow, integrated within the Kadi4Mat research data management platform, to conduct a systematic, FAIR-compliant parametric study of dendritic solidification in the quaternary EN 1.4301 (Fe–Cr–Ni–C) alloy. Thermal conditions—thermal gradient ( G ), solidification velocity ( V s ), and grain misorientation angle ( θ R )—are extracted from a thermocouple-validated ANSYS Fluent weld-pool model and used as inputs to 2D and 3D PACE3D phase-field simulations spanning G from 100 to 900 K/mm, V s from 5 to 40 mm/s, and θ R from 0 ∘ to 45 ∘ . Key findings demonstrate that θ R is a critical parameter—alongside G and V s —governing the cellular-to-dendritic morphological transition, secondary dendrite arm formation, and the topology of inter-dendritic liquid (continuous films versus isolated pockets), each carrying distinct solidification cracking risk pathways. The Kadi4Mat workflow reduces manual pre-processing effort substantially while ensuring data reproducibility and reuse. Quantitative validation against electron probe micro-analysis confirms primary dendrite arm spacing predictions within 12% at the upper weld surface and within 4% at the mid-section.