Imaging of Crystalline Structural Information of Japanese Swords by Pulsed Neutron Transmission Spectroscopy

Japanese swords are peculiar ones forged by a unique method developed in Japan. The forging methods are different each other, depending on age and area. Therefore, the crystalline structure of a Japanese sword depends on the age and the area. In this study, we obtained crystallographic information of Japanese swords and investigated the difference in texture and crystallite size from Japanese swords by using the pulsed neutron transmission spectroscopy. The neutron transmission experiment was carried out at HUNS (Hokkaido University Neutron Source). The samples were two types of Japanese swords. We analyzed the position-dependent neutron transmission spectra and obtained quantitative microstructural information in two-dimensional real space. We found that there were differences of the microstructure between edge and back of each Japanese sword and the microstructure was different between two Japanese swords.