L'intarsio nei marmi ravennati della tarda Antichità e dell’alto Medioevo

Nano-hydroxyapatite coated TiO2 nanotubes on Ti-19Zr-10Nb-1Fe alloy promotes osteogenesis in vitro

Vacuum ultra violet (VUV) emission spectra from plasmas near walls of different metallic materials were measured to estimate the effect upon the local production rate of vibrational excited hydrogen molecules due to plasma wall interaction. Among Cu, Mo, Ni, Ta and Ti, the intensity of band spectrum around Lyman‐α had become the largest when Cu wall was used while it was the smallest for Ti. The role of particle reflection from the plasma electrode surface upon the H− production by a pure electron volume process is discussed.

Pasir Angin site is located in the western part of Java Island kept many artifacts coming from metal materials bronze. Bronze at the site was found in context as a means or equipment worship ancestral spirits. The context also shows that Bronze at the time it was considered a luxury item, and community allegedly Pasir Angin was first exposed to goods of metal materials that are the result of high technology. On this site can not be found the remains of bronze production, so it alleged that no local production of bronze artifacts, but to come from surplus areas such objects and how spreading. Through metallographic analysis showed that bronze objects Pasir Angin site making techniques have similarities with the Dong Son bronze objects. In addition, there were traces of shipping and commercial activities that have ever taken place between the Chinese in this case with Indonesia Dong Son bronze objects strengthens the case originated from the region. Thus the site became Pasir Angin setrategis region that gave birth to early civilizations utilization of high technology. The findings of bronze objects on this site strengthens the case that Java has entered International network since the perundagian.Situs Pasir Angin yang terletak di Pulau Jawa bagian barat banyak menyimpan artefak berasal dari bahan logam perunggu.Perunggu di situs ini ditemukan dalam konteknya sebagai sarana atau perlengkapan pemujaan arwah leluhur.Konteks tersebut juga menunjukkan bahwaPerunggu pada pada masa itu dianggap sebagai barang mewah, dan diduga komunitas Pasir Angin pertama kalinya mengenal barang dari bahan logam yang merupakan hasil teknologi tinggi.Di situs ini tidak ditemukan sisa-sisa produksi perunggu, sehingga muncul dugaan bahwa artefak perunggu bukan produksi lokal melainkan di datangkan dari wilayah yang surplus benda tersebut dan bagaimana persebarannya.Melalui analisis metalografi dapat diketahui bahwa benda perunggu situs Pasir Angin mempunyai persamaan teknik pembuatan dengan benda perunggu Dong Son.Di samping itu adanya jejak-jejak pelayaran dan aktivitas perniagaan yang pernah berlangsung antara Cina dalam hal ini Dong Son dengan Indonesia memperkuat dugaan benda perunggu berasal dari wilayah tersebut.Dengan demikian situs Pasir Angin menjadi wilayah setrategis yang melahirkan peradaban awal pemanfaatan teknologi tinggi. Temuan benda perunggu di situs ini memperkuat dugaan bahwa wilayah Jawa telah masuk jaringan Internasional sejak masa perundagian.

This study concerns metallic objects discovered in 2002 on Amélie beach, Soulac-sur-Mer (Gironde ; Aquitaine). Many Bronze Age hoards have previously been discovered in this area. This find contains thirteen copper base alloy artefacts : eight massive bracelets (three of which present line decoration), a flanged axe, a broken palstave axe, an ingot, a sword fragment and a ring. The flanged axe is typical of production in the Médoc region. The other objects (bracelets, sword and ring) suggest the Duffaits culture. The present contribution concerns a technological study of all the objects : surface observations, metallographic examinations and elementary composition analysis. Fourteen metallographic sections were made according to a specific protocol which, after preparation of the samples, allows the polished sections to be examined before they are etched with a ferric chloride solution. Composition analyses were obtained with an EDXS device associated with a scanning electron microscope. The results enable us to understand the chaînes opératoires used for making these types of flanged axe and massive bracelets. The sequence of the flanged axe shaping processes can be described, and certain gestures and tools clarified. An assembled mould (made with stone or terracotta) was used. After the stripping, a grinding operation, using abrasive materials, was applied to the whole object. Then an annealing and finally a fettling operation – which leaves the metal in a partially hardened state – were applied to the object. No other thermal or mechanical treatment occurred later. This state can be qualified as rough. The technological reading of the set of bracelets confirms their morphological homogeneity by that of the manufacturing processes. The concordance of similar parameters in shape, decoration and shaping techniques allows us to suppose that all the objects were produced in the same workshop. These bracelets were manufactured by a plastic deformation, with the coiling of a bar whose thickness and section shape were certainly conceived from the very moulding. In the very last operation, the decoration was obtained by plastic deformation, on metal softened by annealing. The use of a scriber is very possible. The presence of finished objects and of a rough casting certifies that a local production existed in the area of Soulac-sur-Mer. This technological study allows us to discuss the question of the circulation of metallic objects. The case of the rough axe represents a stage in the chaîne opératoire. This would have been divided into two stages : moulding/ fusion and post-casting. A particular organization would have separated these two stages which would not then have been produced in continuity. We thus submit the hypothesis according to which several types of workshops could have existed, functioning on a «cascade » effect system. An important hierarchical organization of society would in that case be highlighted, with a strong power or authority importing the metallic raw material, centralizing it and, by doing so, being able to control a particular type of workshop making rough-standard axes : the Médoc type axes express rigorous morphometric rules.

Additive manufacturing (AM) refers to an advanced technology used for the fabrication of three-dimensional near-net-shaped functional components directly from computer models, using unit materials. The fundamentals and working principle of AM offer several advantages, including near-net-shape capabilities, superior design and geometrical flexibility, innovative multi-material fabrication, reduced tooling and fixturing, shorter cycle time for design and manufacturing, instant local production at a global scale, and material, energy, and cost efficiency. Well suiting the requests of modern manufacturing climate, AM is viewed as the new industrial revolution, making its way into a continuously increasing number of industries, such as aerospace, defense, automotive, medical, architecture, art, jewelry, and food. This overview was created to relate the historical evolution of the AM technology to its state-of-the-art developments and emerging applications. Generic thoughts on the microstructural characteristics, properties, and performance of AM-fabricated materials will also be discussed, primarily related to metallic materials. This write-up will introduce the general reader to specifics of the AM field vis-à-vis advantages and common techniques, materials and properties, current applications, and future opportunities.