External magnetic fields tailor grain texture in laser powder bed fusion fabricated 316 L alloys

In the present study, the effects of static magnetic fields on melt pool morphology and grain texture in laser powder bed fusion (LPBF)-fabricated 316L stainless steel were investigated. By applying an up to 0.3 T static magnetic field during LPBF, we analyzed the interplay between thermoelectric magnetohydrodynamic (TEMHD) convection and Marangoni flow, and their impact on melt pool morphology, grain orientation, and mechanical properties. Experimental results revealed that a parallel to the build direction magnetic field significantly widens the melt pool while reducing its depth. Electron backscatter diffraction (EBSD) demonstrated that the magnetic field induces rotational dispersion of (111) preferred orientations, weakening crystallographic texture. This texture alteration correlates with a 22 MPa reduction in yield strength, attributed to disrupted Schmid factor distributions. These findings establish magnetic field-assisted LPBF as a viable strategy to tailor grain texture and mitigate anisotropy in additively manufactured metallic components.