From the experimental simulation to integrated non-destructive analysis by means of optical and infrared techniques: results compared

Abstract

In this work the possibility of modeling manufacturing ceramic products is analyzed through the application of transient thermography, holographic interferometry and digital speckle photography, in order to identify the subsurface defects characteristics. This integrated method could be used to understand the nature of heterogeneous materials (such as plastic, sponge simulating a void, wood, aluminum) potentially contained within ceramic materials, as well as to predict crack formation due to them. The paper presents the analysis of green ceramic tile containing defects of different types and sizes located at different depths. The finite element method is used for solving the problem of transient heat transfer occurring in experimental conditions. Unknown parameters of the numerical model (such as convective heat transfer coefficients and sample surface emissivity) were adjusted to obtain numerical simulation results as close as possible to those obtained experimentally. Similarities and differences between experimental and simulated data are analyzed and discussed. Possibilities for improving the results and further developments are proposed.

Holographic Interferometry (HI), Infrared Vision and X-Ray Fluorescence (XRF) spectroscopy for the assessment of painted wooden statues: a new integrated approach

“…It is possible to demonstrate, following the criterion established by the authors in [13], that the detection of the planar coordinates of the B defect (size of the defect) it is possible if the higher-order statistic thermography (HOST) technique (Kurtogram result) with various methods linked to the watershed segmentation concept are combined into a script written in Matlab © environment [56], [66]- [68]. A detailed discussion of the images coming from this method and inherent the present case will be published in the future.…”

“…This work explores the possibility of using the holographic contouring and thermographic methods linked to a digital image processing system [12], recently developed in engineering applications for metrology and three-dimensional surface control [13], in order to determine the position, the shape and the volume of defect B, which was chosen as a reference to analyze the combined approach.…”

“…On the other hand, HOST calculates the higher order centralized moments (3 rd or skewness, 4 th or kurtosis, or n th order moment) of the temporal temperature profiles producing single images summarizing all the relevant information about the original sequence [13], [55]. The segmented Kurtogram [56] containing the B defect was compared to the holographic contouring result for metrology purposes.…”

How to reveal subsurface defects in Kevlar® composite materials after an impact loading using infrared vision and optical NDT techniques?

“…7e) provides complementary information to IRT: the first one for cracks (dotted ellipses) and detachments (dotted circles) detection, while the second one for establishing the shape of the delaminated area linked to fibers distribution. These defects linked to the mechanical stress conditions are defined as satellite defects [36].…”

Infrared exploration of the architectural heritage: from passive infrared thermography to <em>hybrid</em> infrared thermography (HIRT) approach

“…However, in the materials field, important efforts have been made for the retrieval of quantitative information, such as the depth and the size of the defects (6)(7)(8)(9).…”