Semi-in-situ EBSD reveals decoupled morphological and crystallographic texture effects on early plasticity in SLM 316L stainless steel

SLM 316L stainless steel contains a hierarchical microstructure, including columnar grains, EBSD-resolved low-angle boundary networks, and crystallographic texture. How these features jointly control early plastic anisotropy remains unclear. This study investigates the orientation-dependent deformation of stress-relieved SLM 316L using tensile testing and semi-in-situ EBSD. Miniature dog-bone specimens with tensile axes of 0°, 45° and 90° were interrupted at 0%, 2% and 10% engineering strain. Kernel average misorientation, geometrically necessary dislocation density, grain orientation spread, and Schmid-factor-based slip-tendency descriptors were analyzed to separate crystallographic slip tendency from morphological constraint. The 45° specimen showed the highest stress level during early yielding, followed by the 0° specimen, whereas the 90° specimen exhibited the lowest resistance to plastic flow. At 2% strain, the 45° specimen developed the largest increase in median GND density and high-GND area fraction, although the 90° specimen showed the highest maximum Schmid factor, m max , and the strongest multi-slip tendency. This mismatch shows that crystallographic slip tendency alone cannot explain early strain partitioning. From 2% to 10% strain, the 45° specimen also showed the largest increases in GND density and GOS, indicating sustained lattice-curvature accumulation and grain-scale orientation dispersion. Regional analysis further showed that LAGB-associated regions preferentially accumulated GND and KAM at 2%, while this contrast weakened at 10%. These results reveal that early plastic anisotropy in SLM 316L is governed by the coupling between crystallographic slip tendency, columnar morphological texture and retained low-angle boundary network.