Residual Stress Analysis Based on Acoustic and Optical Methods

Area of Science:

• Materials Science
• Mechanical Engineering
• Non-destructive Testing

Background:

• Residual stresses significantly impact material performance and structural integrity.
• Traditional methods for residual stress analysis have limitations in terms of measurement scope and absolute accuracy.
• Acoustoelasticity offers absolute stress measurement but is point-based, while optical interferometry provides full-field deformation data but lacks absolute stress evaluation.

Purpose of the Study:

• To develop a hybrid method combining acoustoelasticity and optical interferometry for quantitative, two-dimensional residual stress analysis.
• To leverage the strengths of both techniques for comprehensive and non-destructive evaluation.
• To validate the proposed method on a dissimilar material joint specimen.

Main Methods:

• Acoustoelasticity was used to determine the elastic modulus at reference points via acoustic velocity measurements.
• Optical interferometry measured the acceleration field under applied tensile load.
• The acceleration field was correlated to residual stresses using harmonic oscillation theory and calibrated with acoustoelasticity data.

Main Results:

• The combined method successfully provided quantitative, two-dimensional residual stress mapping.
• Acoustic and optical measurements showed reasonable agreement in identifying both compressive and tensile residual stresses.
• The study demonstrated the feasibility of non-destructively measuring residual stresses in dissimilar material joints.

Conclusions:

• The co-application of acoustoelasticity and optical interferometry is a feasible and effective approach for advanced residual stress analysis.
• This hybrid technique overcomes the limitations of individual methods, enabling precise, full-field, and non-destructive stress evaluation.
• The findings have significant implications for quality control and structural health monitoring in various engineering applications.