Time filter

Source Type

London, United Kingdom

Fedrigo A.,CNR Institute for Complex Systems | Fedrigo A.,Copenhagen University | Grazzi F.,CNR Institute for Complex Systems | Williams A.,Wallace Collection | And 2 more authors.
Journal of Analytical Atomic Spectrometry | Year: 2015

Neutron Diffraction represents the ideal technique for the characterisation of the micro-structural properties of ancient metals, allowing retrieval of information on the smelting process, and the mechanical and thermal treatments applied during the manufacture of the sample. The object under investigation is a 17th century Japanese helmet (kabuto) from the Haruta School that has already been analysed, along with other six similar examples, using a general purpose neutron diffractometer. Through this study, the quality of the steel (phase composition) was determined and information on the thermo-mechanical treatments applied was inferred, averaging over a scattering volume that affected the entire thickness of the sample. The Haruta kabuto stood out for its very high carbon content, the absence of texture and residual strain, and very big grain size. These factors and the presence of incomplete reduction of the ore sand suggest the presence of plates with a composite structure of layers of steel and iron superimposed. This paper shows the possibility of using neutron diffraction on a highly collimated instrument, such as ENGIN-X (ISIS, UK), to be able to select a very small gauge volume and, this way, to detect variations in the phase composition along the thickness of the plates. Here we present novel results from diffraction measurements by using the instrument ENGIN-X. This study completes the previous cycle of neutron measurements on this sample and sheds light on the structure of the plates. © 2015 The Royal Society of Chemistry. Source

Fedrigo A.,National Research Council Italy | Grazzi F.,National Research Council Italy | Williams A.,Wallace Collection | Scherillo A.,National Research Council Italy | And 2 more authors.
Journal of Analytical Atomic Spectrometry | Year: 2013

In this work we present an extensive time of flight neutron diffraction (ToF-ND) study on some Japanese armour components. The experiments were carried out at the INES diffractometer at ISIS, the pulsed neutron source in the UK. In particular, we have studied seven Japanese helmets (kabuto) made between the 16th and 17th century. By means of this non-invasive approach we have been able to determine quantitatively the phase composition and the microstructural properties of these artefacts. The samples belong to different periods and different levels of quality. The observed differences were quantified in terms of the accuracy and amount of their working. A quantitative determination of their phases and of the thermo-mechanical treatments has been obtained for all investigated samples, confirming that the use of ToF-ND represents one of the most suitable non-destructive approaches for the characterization of metal archaeological artefacts. © 2013 The Royal Society of Chemistry. Source

Leroy S.,CEA Saclay Nuclear Research Center | Leroy S.,Synchrotron Soleil | Simon R.,Karlsruhe Institute of Technology | Bertrand L.,Synchrotron Soleil | And 3 more authors.
Journal of Analytical Atomic Spectrometry | Year: 2011

To elucidate the origin of armours supposed to be from Lombardy according to art-historians, the very small Slag Inclusions entrapped in the metallic matrix were analysed on the samples taken on armours. This paper presents the analytical protocol, based on the coupling of LA-ICP-MS and confocal SR - XRF (confocal Micro-X-ray fluorescence under Synchrotron Radiation) developed to obtain trace element information from this kind of inclusion. Confocal SR - XRF has been applied to inclusions of ancient iron artefacts for the first time. The reliability and reproducibility of the procedure developed for the trace elements quantifying have been checked by a comparison of the results obtained by LA-ICP-MS and by confocal SR - XRF. Our first results allow us to draw some preliminary observations on the origin of the samples. © 2011 The Royal Society of Chemistry. Source

Salvemini F.,CNR Institute for Complex Systems | Salvemini F.,University of Florence | Grazzi F.,CNR Institute for Complex Systems | Fedrigo A.,CNR Institute for Complex Systems | And 7 more authors.
European Physical Journal Plus | Year: 2013

We present novel results from a non-invasive examination of two kabuto (helmets), made in Japan in the 17th century. Neutron-imaging experiments (radiography and tomography), carried out at the ICON and NEUTRA beamlines, operating at the neutron source SINQ (CH), have allowed to determine the inner metal structure and manufacturing techniques of these beautiful examples of past technology, revealing some otherwise invisible details. © 2013, Società Italiana di Fisica and Springer-Verlag Berlin Heidelberg. Source

Barzagli E.,CNR Institute for Complex Systems | Barzagli E.,University of Florence | Grazzi F.,CNR Institute for Complex Systems | Williams A.,Wallace Collection | And 4 more authors.
Applied Physics A: Materials Science and Processing | Year: 2015

The evolution of metallurgy in history is one of the most interesting topics in Archaeometry. The production of steel and its forging methods to make tools and weapons are topics of great interest in the field of the history of metallurgy. In the production of weapons, we find almost always the highest level of technology. These were generally produced by skilled craftsmen who used the best quality materials available. Indian swords are an outstanding example in this field and one of the most interesting classes of objects for the study of the evolution of metallurgy. This work presents the study of a Shamsheer (a sword with a curved blade with single edge) made available by the Wallace Collection in London. The purpose of this study was to determine the composition, the microstructure, the level and the direction of residual strain and their distribution in the blade. We have used two different approaches: the classical one (metallography) and a nondestructive technique (neutron diffraction): In this way, we can test differences and complementarities of these two techniques. To obtain a good characterization of artifacts studied by traditional analytical methods, an invasive approach is required. However, the most ancient objects are scarce in number, and the most interesting ones are usually in an excellent state of conservation, so it is unthinkable to apply techniques with a destructive approach. The analysis of blades that has been performed by metallographic microscopy has demonstrated the specificity of the production of this type of steel. However, metallographic analysis can give only limited information about the structural characteristics of these artifacts of high quality, and it is limited to the sampled areas. The best approach for nondestructive analysis is therefore to use neutron techniques. © 2015, Springer-Verlag Berlin Heidelberg. Source

Discover hidden collaborations