Extended Data Fig. 8: In situ neutron diffraction measurements at room temperature (RT) and 20 K conducted at TAKUMI.

a, Schematic of the experimental setup. Neutron diffraction patterns along both the loading direction (LD) and the transverse direction (TD) can be obtained at the same time during uniaxial mechanical testing. b, Stress–displacement curves measured at RT and 20 K, respectively. c-f, In situ neutron diffraction patterns from LD and TD detectors obtained at both RT and 20 K, with the specimen held at positions indicated as spot 1, spot 2, spot 3, and spot 4 in b. The comparison of diffraction patterns at RT and 20 K suggests that the crystal structures of the parent phase and the martensite phase remain essentially unchanged at the tested temperatures.