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This paper presents a study carried out on the painted altarpiece preserved inside the Basilica of Santa Maria in Cosmedin, Rome, by combining three imaging techniques operating in the near‐ and mid‐infrared spectral ranges. The altarpiece has several pictorial layers and restorations, which have superimposed over time for stylistic adjustment and conservative purposes up to its present appearance. The results obtained in this study enable the detection of damage to the wooden support and the identification of pictorial features buried beneath the visible paint layer, thus providing significant information on the historical and artistic characterization of the artefact. [ABSTRACT FROM AUTHOR]

In this paper, a new method based on the use of infrared thermography is proposed for the characterization of repairs and inserted parts on ancient bronzes. In particular, the quality of the contact between different kind of insertions and the main body of bronze statues is investigated by analysing the heat conduction process occurring across the interface between them. The thermographic results have been used to establish the nature of these inserted elements and the way they have been coupled to the main body of the statue during and after the manufacturing process. A model for the heat conduction based on the numerical finite elements method has been applied to compare the obtained results to the theoretical predictions. Measurements have been first carried out on test samples and then in the field on the Boxer at Rest ( Museo Nazionale Romano in Rome), a masterpiece of the Greek Statuary, which contains a large variety of inserted items and repairs which are typical of the manufacturing process of bronze artefacts in general. [ABSTRACT FROM AUTHOR]

Pulsed infrared thermography was applied to the analysis of the Capitoline She Wolf bronze statue, in the collection of the Musei Capitolini in Rome. We show how it can be used to study the bronze alloy properties and several subsurface and structural features of the statue such as casting faults and repairs providing information useful to recover the steps of the manufacturing process. In particular, the thermal diffusivity of the alloy was determined and quantitative evaluations were carried out concerning the thickness of the bronze in various parts of the statue, the depth of cavities originating from air bubbles in the casting melt and the profile of the contact area of some patches applied to mend gaps left after the casting process. Finally the obtained thermal diffusivity value was discussed in relation to the actual bronze composition of the She Wolf statue and it was shown to be consistent with the trend of values expected for different copper alloy compositions. [ABSTRACT FROM AUTHOR]

Active infrared thermography is an important non-destructive technique frequently employed in the analysis of cultural heritage. For its capability to show subsurface features in the artifacts, this technique has been used to investigate various kinds of artifacts, composed of different structures and materials. In this work, an overview of its recent applications is presented. In particular, the detection of cold working features in bronze sculpture investigations, of buried features in ancient book bindings, such as their structural characteristics and written scraps re-used in their manufacturing process, and on the investigation of defects and inhomogeneities in illuminations, is reported. [ABSTRACT FROM AUTHOR]

• Pulsed infrared thermography. • Thermal diffusivity measurements carried out on specifically prepared bronze specimens. • Electrical conductivity measurement by means of an Eddy current technique. • Nondestructive procedure for the evaluation of ancient bronze alloys composition. In this work, we report on the application of Pulsed Infrared Thermography for the analysis of the thermal diffusivity dependence on the composition of copper alloys with tin (Sn) and lead (Pb) concentrations typical of ancient bronze artefacts. To this aim, specifically prepared bronzes samples have been investigated. Both the measured thermal diffusivity values and those retrieved from the literature showed a decreasing trend with increasing Sn and Pb concentration. In the overall data analysis, the concentration of Pb atoms was weighted by a coefficient to account for their lower efficiency in reducing the thermal transport properties of the alloy with respect to the Sn atoms. Electrical conductivity values measured on the same samples showed a dependence very similar to that obtained for the thermal conductivity, pointing out the mainly electronic nature of the thermal conductivity in such samples. [ABSTRACT FROM AUTHOR]

Infrared thermography (IRT) is a non-destructive technique that has recently been extensively applied to the investigation of cultural heritage. It provides information on the surface and subsurface structure of the artefacts by the analysis of the heat diffusion process within the sample. IRT has been successfully applied to the study of historic large structures and buildings most of the time by means of the so-called passive approach, where only the naturally occurring temperature changes in the sample are analysed. On the other hand, IRT has also been applied to the study of other art and historic artefact by applying the so-called active method where the thermal stimulation of the sample is required. In this article, an overview of the applications of active thermography to the investigation of art and historic artefacts will be presented and discussed. [ABSTRACT FROM AUTHOR]

A remote and non-destructive method for the characterization of residual stress in metallic components is here proposed. Such a method is based on the application of infrared thermography for the evaluation of thermal diffusivity, which is expected to be dependent on the local dislocation density in the material lattice induced by plastic deformations. Preliminary experimental results obtained on a yielded ASTM 516 grade 65 steel specimen are presented and discussed on the basis of microhardness and optical metallographic investigations carried out on the same sample. [ABSTRACT FROM AUTHOR]

• Detection of hidden texts buried into paper based cultural heritage artefacts. • Analysis of the 3D heat diffusion in optically semi-transparent materials. • Study of the distortions in the thermographic images of subsurface graphic features. Pulsed thermography has proven to be a useful tool to detect subsurface features in ancient bookbindings and, in particular, to provide the IR image of texts buried beneath the end - leaves of the books. In this paper the theory is presented to analyze the influence of the geometrical and physical parameters involved in the processes leading to the distortion in the IR image of the detected buried graphical features. The distortion is mainly due to the lateral diffusion of the heat generated at the ink feature after the absorption of an excitation light. A comprehensive analysis taking into account the three dimensional heat diffusion process, in an optically semi-transparent medium, is considered. Numerical results are reported showing the behavior of the contrast and of a distortion parameter of the buried inked feature detected by the IR imaging in the various considered cases. [ABSTRACT FROM AUTHOR]

In this paper, the thermographic results obtained by studying some masterpieces of the bronze statuary of Rome are presented. More specifically, a quantitative approach has been adopted in the investigation of the Capitoline She Wolf, hosted in the Musei Capitolini, and of the Boxer at Rest and the Hellenistic Prince belonging to the collection of the Museo Nazionale Romano. The obtained results provided data useful to characterize the properties of the bronze alloy and several subsurface features of the statue, such as casting faults and patches. In particular, the interface between different kind of patches and the main body of the statue has been investigated in order to determine the way they were applied. Moreover, the thermal diffusivity of the alloy of the Capitoline She Wolf has been evaluated and quantitative investigations have been carried out in order to determine the depth of some features, such as the cavities originating from air bubbles in the casting melt. [ABSTRACT FROM AUTHOR]