Assessment of Destructive and Non-Destructive Residual Stress Measurements for WAAM Components
Residual stress measurements from both methods show strong agreement, providing valuable input for finite element models (FEM) of the process. Neutron diffraction enables non-destructive subsurface and bulk measurements, but its accuracy heavily depends on the preparation of stress-free reference samples. A detailed analysis of these reference samples revealed a strong crystallographic texture, though the overall variation remained small across the height of the WAAM component.
The contour method, in contrast, is unaffected by texture or chemical composition variations, offering a key advantage over diffraction-based techniques. However, as a destructive method, it is limited to measuring residual stress in a single direction. This study discusses the strengths and limitations of both techniques in the context of WAAM, particularly regarding spatial resolution, reference sample requirements, and applicability to large-scale components.
By refining residual stress measurement methodologies and identifying key constraints, this study advances the approach to residual stress assessment in WAAM printed structures. These findings contribute to improved process control and enhance structural reliability in additive manufacturing for civil and structural applications.