A Spatially Modulated Structure during the Martensitic fcc-fct Transformation in Fe–Pd Alloy

抄録

A detailed X-ray diffraction investigation has been carried out in the vicinity of fcc to fct phase transition temperature in Fe–Pd alloys in order to elucidate the premartensitic phenomena. Using a high-resolution spectrometer and with fine temperature control, the temperature dependence of the splitting of Bragg reflection as well as diffuse scattering were measured in detail. Just above the martensite transformation temperature, we found a new intermediate phase. This structure is characterized by a coherent mixture of the two kinds of tetragonal lattices with different tetragonality and is interpreted as a spatially modulated fct phase.