[3L05-08] Neutron Application

[3L08] Development of an evaluation method of martensite phase fraction in a ferritic steel by pulsed neutron transmission spectroscopy

*Atsuya Kusumi¹, Hirotaka Sato¹, Hirotoshi Hayashida², Kenichi Watanabe³, Takashi Kamiyama¹, Yoshiaki Kiyanagi³ (1. Hokkaido Univ., 2. CROSS, 3. Nagoya Univ.)

Keywords:Pulsed neutron imaging, Bragg edge, Profile analysis, Ferrite, Martensite, Crystalline phase fraction

The pulsed neutron transmission spectroscopy can provide information of crystalline microstructure by analyzing Bragg edges included in a neutron transmission spectrum. However, Bragg edges caused by two crystalline phases are overlapped when each phase included in a sample has similar crystal structural parameters. Thus, it is difficult to evaluate the ratio of each phase from such data by a conventional analysis method. In this study, we developed a new profile fitting analysis method to analyze overlapped Bragg edges from ferritic and martensitic phases which had similar crystal structures and slightly different Bragg edge profiles. This method can evaluate the ratio of each phase from the overlapped Bragg edges by reconstructing them based on the Bragg edge profile of each phase.