Neutron diffraction for cultural heritage

Full text: Neutrons represent a special interest for studies of objects of cultural heritage due to their high penetration ability. Depending on material they can penetrate up to 10 cm and more providing crystallographic information about material in the interior non-destructively. This cannot be attained by other techniques (x-rays, EBSD, optical microscopy) that can work only on surface and frequently requiring surface preparation/modification. Material such as metals (bronzes and steels of historical weapon blades, gold and silver coins), ceramics and rocks can be studied with neutron diffraction to determine grain crystallographic alignment, phase composition and internal stresses. These characterisations can forensically reveal the processes and conditions of the studied cultural heritage object production. Several neutron diffraction techniques (and neutron diffraction instruments) are available at the Australian neutron research facility based on the OPAL research reactor at ANSTO (Lucas Heights). The suite of diffractometers includes high-resolution powder diffractometer (ECHIDNA), high-intensity diffractometer (WOMBAT), single-crystal diffractometer (KOALA) and stress/texture diffractometer (KOWARI). Over last years of operation the residual stress diffractometer KOWARI has been steadily used for research of cultural heritage objects and few recent projects will be featured in the presentation. (author)