KINETICS OF THE MARTENSITIC TRANSITION IN IN-TL ALLOYS

The kinetics of the martensitic transition in In-Tl alloys has been studied by x-ray- and neutron-diffraction methods. A characteristic waiting time appears at fixed temperature above M(s), the normal martensitic phase transition start temperature. A similar waiting time is also seen for inverse phase transitions. A peculiar temperature T(p), which is above M(s), but below T(o), is found to exist. The time development of x-ray-diffraction patterns shows a very different behavior whether the temperature is above T(p) or below T(p). It is found that ideal nucleation and growth take place between T(p) and T(o). Between T(p) and M(s), the kinetics of the phase transition is more complicated. In order to understand the kinectics of the phase transition, the temperature-dependent waiting time curve in In-Tl alloys is calculated using the Roitburd method [A. L. Roitburd, Mater, Sci. Eng. A127, 229 (1990)] and is found to be in good agreement with experimental results.