High-resolution 3D strain and orientation mapping within a grain of a directed energy deposition laser additively manufactured superalloy

The industrialization of Laser Additive Manufacturing (LAM) is challenged by the undesirable microstructures and high residual stresses originating from fast complex solidification process. Non-destructive assessment mechanical performance controlling deformation patterning therefore critical. Here, we use Dark Field X-ray Microscopy (DFXM) to map 3D subsurface intragranular orientation strain variations throughout a surface-breaking grain within directed energy deposition nickel superalloy. DFXM results reveal highly heterogenous microstructure in terms local lattice strain. comprises ≈ 5 μm-sized cells with alternating states, as ×10−3, differences <0.5°. are compared Electron Backscatter Diffraction measurements same its cut-off surface. We discuss developments during LAM, rationalising development extreme thermal gradients processing susceptibility for solute segregation.