Neutron Strain Scanning of Archaeological Bronzes

We report neutron strain scanning experiments on archaeological bronzes, with the aim of identifying the original manufacturing techniques used. The specimens studied were a Picenan necklace from VI BC, and an Etruscan bucket handle from IV BC, exhibited at the Marches Museum of Archaeology, Ancona, Italy. Time-of-flight neutron diffraction and transmission experiments were performed at the ENGIN-X instrument, ISIS, UK. For the necklace, characteristic bending strain profiles and a small degree of preferred orientation indicate that the specimen had been cold worked. For the handle, broad diffraction peaks and highly distorted Bragg edges -typical of a columnar grain microstructure- suggested that this specimen was cast and did not undergo significant thermal or mechanical treatment. The relation between the experimental diffracted and transmitted time-of-flight spectra, and the microstructure of specimens are discussed.