Accuracy and sensitivity of a hole drilling and digital speckle pattern interferometry combined technique to measure residual stresses

• Published in: Optics and lasers in engineering Vol. 41; no. 2; pp. 297 - 305
• Main Authors: Viotti, M.R., Kaufmann, G.H.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-02-2004; Elsevier
• Subjects: Digital speckle pattern interferometry; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Hole drilling; Imaging and optical processing; Instruments for strain, force and torque; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Interferometers; Mechanical instruments, equipment and techniques; Optical instruments, equipment and techniques; Optical metrology; Optics; Phase shifting; Phase shifting interferometry; Physics; Residual stresses; Speckle and moire patterns; Phase shifting; Residual stresses; Digital speckle pattern interferometry; Hole drilling; Optical metrology; Stress analysis; Industrial application; Phase shifting interferometry; Machining; Optical method; Metrology; Experimental device; Experimental study; Speckle interferometry; Boring; Stress measurement
• ISSN: 0143-8166; 1873-0302
• DOI: 10.1016/S0143-8166(02)00173-2

This paper reports on the accuracy and sensitivity of digital speckle pattern interferometry (DSPI) when it is combined with the hole drilling technique for measuring residual stresses. The in-plane displacement field generated by the introduction of a small hole is determined using an automated data analysis approach. This method is based on the calculation of the optical phase distribution through a phase-shifting method and the application of a robust iterative phase unwrapping algorithm. It is experimentally demonstrated that residual stresses can be measured with a relative uncertainty of 7.5%. It is also shown that the minimum value of residual stress that can be determined with the DSPI and hole drilling combined technique is about 10% of the yield stress of the material.