Measurements of Carbon Content and Retained Austenite Volume Fraction in Steels by Neutron Bragg-edge Transmission Analysis at a Compact Neutron Source, AISTANS

Abstract

Neutron Bragg-edge transmission analysis was performed at a newly constructed compact neutron source, AISTANS, for 30Mn-C austenitic steels and ferrite-bainite-retrained austenite (TR) steels, which had previously been measured at BL22, RADEN, in J-PARC MLF. Employing a newly developed 2D Li-glass neutron detector, Bragg-edge spectra were obtained at 1 kW electron-beam operation of AISTANS. The obtained profiles were analyzed using the RITS code. In 30Mn-C steels, the determined lattice parameters were found to show a linear dependence with carbon content, similarly to the results obtained at RADEN. In TR steels, Bragg-edge spectra obtained from three orthogonal directions were differently shaped each other stemmed from the texture. Reasonable fitting was obtained only in the cases in which the influence of texture was weak; the profile obtained along the rolling direction or averaged one of the three directional results.