Abstract Laser powder bed fusion (LPBF) imposes steep thermal gradients, resulting in distortion and the formation of significant residual stresses, which often precipitate in-situ cracking at support interfaces and sharp geometric features. To isolate their influence on structural integrity, we combined fracture mechanics testing with residual stress evaluation on as-built compact tension specimens printed in two orthogonal orientations. The experimentally measured apparent stress-intensity factor was deconvolved into mechanical and residual-stress components, yielding a residual-stress-free fracture toughness (K₈₂₄₅₅ K ICeff). Apparent fracture toughness (K₈₂) K IC) ranged from 25 to 35 MPa m 1/2, whereas K₈₂₄₅₅ K ICeff increased to 45–52 MPa m 1/2. Residual stresses, therefore, depress the material’s residual-stress-free resistance by up to ~ 50% and accentuate orientation-dependent anisotropy. The framework presented offers a route for quantifying process-induced toughness degradation in LPBF alloys.
Louw et al. (Mon,) studied this question.