70 research outputs found
Metal alloys, matrix inclusions and manufacturing techniques of Moinhos de Golas collection (North Portugal): a study by micro-EDXRF, SEM–EDS, optical microscopy and X-ray radiography
"Article:820"A collection of 35 metallic artefacts comprising
various typologies, some of which can be attributed to the
Bronze Age and others to later periods, were studied to
provide detailed information on elemental composition,
manufacturing techniques and preservation state. Elemental
analysis by micro-EDXRF and SEM–EDS was performed
to investigate the use of different alloys and to
study the presence of microstructural heterogeneities, as
inclusions. X-ray radiography, optical microscopy and
SEM–EDS were used to investigate manufacturing techniques
and degradation features. Results showed that most
of the artefacts were produced in a binary bronze alloy
(Cu–Sn) with 10–15 wt% Sn and a low concentration of
impurities. Other artefacts were produced in copper or in
brass, the latest with varying contents of Zn, Sn and Pb. A
variety of inclusions in the metal matrices were also found,
some related to specific types of alloys, as (Cu–Ni)S2 in
coppers, or ZnS in brasses. Microstructural observations
revealed that the majority of the artefacts were subjected to
cycles of thermomechanical processing after casting, being
evident that among some artefacts different parts were
subjected to distinct treatments. The radiographic images
revealed structural heterogeneities related to local corrosion
processes and fissures that seem to have developed in
wear-tension zones, as in the handle of some daggers.
Radiographic images were also useful to detect the use of
different materials in one particular brass artefact, revealing
the presence of a possible Cu–Sn solder.This work was funded by FEDER funds through
the COMPETE 2020 Programme and National Funds through FCT—
Fundação para a Ciência e a Tecnologia under the project UID/CTM/
50025/2013 to CENIMAT/I3N. C2
TN/IST authors gratefully
acknowledge the FCT support through the UID/Multi/04349/2013
project. EF acknowledges FCT for the grant SFRH/BPD/97360/2013.
JF acknowledge FCT for the grant SFRH/BD/65143/2009. Part of this
project has been done in the framework of the FCT project ENARDAS
(PTDC/HISARQ/112983/2009).info:eu-repo/semantics/publishedVersio
Copper Metallurgy in the Jordan Valley from the Third to the First Millennia BC: Chemical, Metallographic and Lead Isotope Analyses of Artefacts from Pella
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