Ti-Nb alloys are excellent candidates for biomedical applications such as implantology and joint replacement because of their very low elastic modulus, their excellent biocompatibility and their high strength. A low elastic modulus, close to that of the cortical bone minimizes the stress shielding effect that appears subsequent to the insertion of an implant. The objective of this study is to investigate the microstructural and mechanical properties of a Ti-Nb alloy elaborated by selective laser melting on powder bed of a mixture of Ti and Nb elemental powders (26 at.%). The influence of operating parameters on porosity of manufactured samples and on efficacy of dissolving Nb particles in Ti was studied. The results obtained by optical microscopy, SEM analysis and X-ray microtomography show that the laser energy has a significant effect on the compactness and homogeneity of the manufactured parts. Homogeneous and compact samples were obtained for high energy levels. Microstructure of these samples has been further characterized. Their mechanical properties were assessed by ultrasonic measures and the Young's modulus found is close to that of classically elaborated Ti-26 Nbingot.

The Neolithic tomb of Gavrinis is famous for its rich and complex engraved art that has inspired a large number of interpretative studies. However, all of these are based on unsatisfactory drawings. This article describes the methodological results of a new project for recording the Gavrinis engravings that combines 3D laser and 2D photographic techniques. Laser scanning not only provides accurate contextual information such as the stone relief and architectural setting in which the art is found. Specially designed processing of point clouds also makes it possible to highlight the contours of the pecked motifs and to record them directly from the 3D model of the decorated stones. This can be further improved by photography using oblique lighting and image processing techniques in order to obtain more detailed recordings of the motifs as well as insights into their chronological relationships. In the unusual case of barely visible engravings made with very slight peckmarks, experimental application of the DStretch colour detection programme has been unexpectedly successful. A comparison of all these results shows that laser and photographic techniques have different strengths and weaknesses that complement each other. Thus, combined use of these techniques within a single methodological process produces innovative and comprehensive documentation of Neolithic tomb art.