Application of digital speckle interferometry to visualize surface changes in metallic samples immersed in Cu(NO3)2 solutions

Abstract

Digital speckle pattern interferometry (DSPI) has been applied to analyze surface corrosion processes in a metallic sample immersed in a 0.1 M CuðNO 3 Þ 2 solution. The corrosion process induces changes in the surface and in the solution refractive index. A detailed analysis of the DSPI measurements has been performed to obtain a two-dimensional visualization of the surface changes and an evaluation of the refractive index changes of the solution. The possibilities of DSPI for measuring surface changes in these conditions have been analyzed.

Applications of windowed Fourier fringe analysis in optical measurement: A review

“…In [16], the ESPI was used to visualize surface changes in metallic samples immersed in Cu(NO 3 ) 2 in order to accurately measure local corrosion rates and localize the corroding sites. The spatial FT was used for phase extraction and the WFF2 was used for denoising.…”

Possibilities and limitations of digital speckle pattern interferometry in the analysis of corrosion processes in metallic materials

“…In this sense, digital speckle photography has been applied to visualize the local surface changes by recording the evolution of the correlation coefficient [8][9][10]. Digital speckle pattern interferometry (DSPI) has been used to obtain information on the changes at all points of the sample surface simultaneously [11][12][13].…”

“…In this case, measurements were performed in air after having extracted the sample from the liquid. Some attempts have been made to detect changes in metallic surfaces immersed in liquid corrosive solutions [13]. In this work, the applicability of DSPI for studying the corrosion process evolution while the sample is kept immersed in the solution has been investigated.…”

Surface Characterization Techniques: A Systematic Review of their Principles, Applications, and Perspectives in Corrosion Studies

“…Other QPM and surface measurement techniques.-Aside from the well-researched AFM, VSI, and DHM techniques, there are other varieties of QPM and surface measuring systems, as shown in Table IV that would be relevant for discussion, including in situ scanning tunneling microscopy (STM), 119,[121][122][123] confocal laser scanning microscopy (CLSM), 114,[116][117][118] digital holography (DH) 102,104,105 digital speckle pattern interferometry (DSPI), [100][101][102] in situ special modulation interferometry (SMI) 124 and in situ light reflectivity microscopy, 125,126 etc. Interestingly, their working principles or mode of operation are quite similar to the three systems (AFM, VSI, and DHM) earlier discussed above.…”