Dislocation monitoring during deformation and new sample environment device for engineering studies

Harjo, S.   ; Kawasaki, Takuro   ; Tomota, Yo*; Shibata, Akinobu*; Tsuji, Nobuhiro*; Aizawa, Kazuya  

Two topics done at TAKUMI of MLF, J-PARC are introduced. Evolutions of dislocation characteristics during tensile deformation in a lath martensitic steel have been possible to be monitored by applying the convolutional multiple whole profile (CMWP) fitting method, to understand the strengthening behavior of metallic material with extremely high dislocation density induced during the material preparation. This method is possible to be applied to understand the deformation behaviour of bulk nano materials. A new sample environmental device for simulating Thermo-Mechanical Controlling Process of materials (thermec-mastor) has been installed in a collaboration between a research group in Kyoto University and TAKUMI. This new device is designed to heat and cool a specimen rapidly, and to apply compression with a high strain rate. The basic design and the commissioning progress of the thermec-mastor will be briefly introduced together with the first neutron diffraction data on steels.