Digital Image Correlation for Measuring Full-Field Residual Stresses in Wire and Arc Additive Manufactured Components

Area of Science:

• Materials Science
• Mechanical Engineering
• Non-Destructive Testing

Background:

• Wire and Arc Additive Manufacturing (WAAM) is a growing technology for producing large metal components.
• Residual stresses in WAAM parts can significantly impact their mechanical performance and structural integrity.
• Accurate measurement of these stresses is crucial for quality control and performance prediction.

Purpose of the Study:

• To demonstrate the capability of Digital Image Correlation (DIC) for full-field residual stress evaluation in WAAM components.
• To investigate the influence of component geometry (wall height) on residual stress distribution.
• To validate the DIC-based residual stress measurement technique against established methods.

Main Methods:

• WAAM steel walls of two different heights (24 mm and 48 mm) were fabricated on clamped substrates.
• Digital Image Correlation (DIC) was employed to capture out-of-plane deformation during component unclamping.
• Residual stresses were calculated from the strain field data obtained via DIC.

Main Results:

• DIC successfully captured the bending deformation of WAAM parts upon release from clamping.
• The DIC-based method provided quantitative full-field residual stress distributions.
• Results from DIC were consistent with analytical models and validated by contour method and X-ray diffraction.

Conclusions:

• Digital Image Correlation (DIC) is a viable and effective technique for measuring full-field residual stresses in WAAM components.
• The study confirms the utility of DIC for non-destructive residual stress analysis in additively manufactured structures.
• DIC offers a powerful tool for understanding and managing residual stresses in WAAM parts, improving their reliability.