No abstract

The characterization of materials constituting cultural artefacts is a challenging step in their conservation, due to the object’s uniqueness and the reduced number of conservation institutes able to supply non-destructive analysis. We propose an alternative analytical tool, which combines accessibility (low cost and portable) and high sensitivity, based on electrochemical linear sweep voltammetry (LSV) with paraffin impregnated graphite electrode (PIGE). To investigate the composition of “white alloys” that certainly have been used as decoration on copper-based Roman fibulae, sampling was done very locally by gently rubbing the selected areas with the PIGE. LSV results evidence the presence of silver, lead, and tin, supporting the argument provided by typological analysis that these metals were used for decoration

No abstract

Infiltration of silica‐based refractory cores with colloidal boehmite slurry has the effect of greatly reducing sintering shrinkage, as required for precision casting. Only 300 ppm of equivalent alumina is sufficient to decrease the shrinkage from RT to 1600°C more than three‐fold. Microstructural observations and XPS measures show that the silica grains are homogeneously coated with a reaction film which hinders viscous flow.