In situ lattice strain mapping during tensile loading using the neutron transmission and diffraction methods

In this study, the change in internal lattice strain in an iron plate during tensile deformation was investigated by performing in situ measurements under applied force. The lattice strain was evaluated by neutron diffraction and Bragg-edge transmission. The neutron diffraction results showed that the averaged 110 lattice strain along the direction perpendicular to the applied force was between -422 and -109 × 10^-6. The position dependence of the lattice strain and the change in the distribution of elastic strain in an iron plate with notches during tensile deformation was obtained by Bragg-edge transmission. It was also observed that, when the load increased over 30 kN, the area of plastic deformation increased around the positions of the notches.