Towards a comprehensive interpretation of wavelength dependent attenuation coefficients: The effect of dislocation densities

Hydrogen embrittlement in metal alloy can generate microstructural change, resulting in residual stress in the bulk. However, the quantitative measurement on H-uptake is very challenge due to very low sensitivity of common analytical technique. Prior to the understanding of H-uptake in metal alloy, an underlying behavior of stress-strain in metal alloy should be studied. Defects and dislocations in metal alloys using neutron transmission has been found limited. Since neutron transmission can probe a sample in a large volume at once compared to neutron scattering, diffraction, and spectroscopy, it is useful to obtain a stress-strain mapping in the sample which results in more underlying knowledge on defect distribution. In addition, an in-situ measurement would allow us to study an evolution of stress and to quantitatively measure how neutron transmission coefficient correlates to the residual stress. The proposed study will study on a Medium manganese steel established in the 3rd generation high strength steel (AHSS) as well as a low carbon steel as a reference material.