Speaker
Mr
Genki Hori
(Nagoya University)
Description
**Introduction**
In the case of iron cultural properties such as Japanese sword and matchlock gun, manufacturing techniques and material characteristics are not clear. To get detailed information about crystallographic characteristics of those iron artifacts is desired for elucidating them. In the analysis of precious iron cultural properties, nondestructive evaluation is preferable.
Neutron has high penetrating power, and it is possible to get inside information nondestructively. Moreover, by using pulsed neutron transmission spectroscopy, we can obtain crystallographic information by analyzing the low-energy neutron transmission spectra including Bragg edges. The position and the shape of the Bragg edge give information such as strain, crystallite size, texture and density.
It is considered to be useful to study such crystallographic parameter change of iron parts during making process to consider the effect of the making process to the crystallographic characteristics. Based on such information we will be able to guess the making process by the crystallographic information. We performed pulsed neutron transmission experiments for iron parts at different making stages and analyzed the transmission data by using the RITS code [1] to obtain crystallographic information.
**Experimental**
Neutron experiments were performed at NOBORU beam line at J-PARC Material and Life Science Experimental Facility in Japan. Ten iron samples at different making stages were cut-out from Japanese swords made with the same process. The sample was placed in front of a two-dimensional position sensitive detector, and the transmission spectra of the pulsed neutrons were measured by the time-of-flight method.
**Results**
Here, we concentrate on the crystal lattice spacing since it will be affected by hammering and quenching. In the sample before quenching, the crystal lattice spacing shows minimal around the center between the cutting edge and the back of the blade. The trend may be due to hammering. In the sample after the quenching, the lattice spacing around the cutting edge became larger with approaching the end of the edge. This increase is clearly attributed to content of martensite phase. We obtained such spatial dependent change from ‘pilling and melting’ to ‘Kaji Togi (Adjusting the shape).
[1] H. Sato, T. Kamiyama, Y. Kiyanagi, Materials Transactions, Vol. 52, No. 6, pp. 1294-1302, (2011)
Primary author
Mr
Genki Hori
(Nagoya University)
Co-authors
Prof.
Akira Uritani
(Nagoya University)
Prof.
Atsushi Yamazaki
(Nagoya University)
Prof.
Kenichi Watanabe
(Nagoya University)
Prof.
Manako Tanaka
(Showa Women's University)
Prof.
Yoshiaki Kiyanagi
(Nagoya University)
