Deposition-induced incompatibility in additive manufacturing

This work investigates the kinematic mechanism by which additive manufacturing generates persistent strain incompatibility, the source of self-equilibrated residual stress in an unloaded, thermally homogeneous body. By shifting focus from strain to displacement, the formulation treats deposition as the attachment of unstressed material to a prestressed, predeformed substrate, allowing incompatibility to accumulate even when plasticity is deliberately suppressed. The role of deposition velocity is qualitatively assessed via geometrically nonlinear finite-element simulations and Laser Metal Deposition experiments, showing consistent deformation trends. The framework complements inherent strain methods by accounting for the distinctive mechanics of growing bodies.