| Abstract Scope |
This research investigates the applicability of the ψ² method for in-situ, non-destructive residual stress analysis via X-ray diffraction (XRD) during powder-based directed energy deposition (DED) of 316 stainless steel powder onto a matching substrate, representative of remanufacturing scenarios. Unlike conventional, destructive post-process techniques, like the contour method, in-situ XRD enables real-time tracking of lattice strain during deposition. The ψ² method, using lateral tilts, is unique in its ability to obtain data when reorienting the sample is not possible (i.e. during deposition). Single-layer depositions were examined to isolate the effects of localized thermal cycles and heat affected zones (HAZ). This was compared to measurements after cooling, once the residual stress profiles stabilized, showing high tensile residual stresses in the melt pool region and lower-magnitude compressive stress in adjacent HAZs. Quantifying residual stress throughout and after the deposition can inform deposition parameters and stress control in remanufactured components. |