A nucleation model associated with phase transitions in the indium-rich and Au-Cu-Zn alloys
This paper is concerned with the calculation of the critical radius and the wavelength of modulation associated with the strained inclusion during first order phase transition. For this purpose the forth order spatial gradient term was included into the free energy density inside the inclusion. Numerical results were obtained for indium-rich alloys such as In-21 at.% Tl, In-4.4 at.% Cd and In-(13−X) at% Pb-X at.% Sn, and also the alloy Au-30 at.% Cu-47 at.% Zn. The effect of the temperature and the atomic fraction of alloying element on critical radius and wavelength of modulation is also discussed and compared to the experimental results.
Abstract An experimental study of convective effects in horizontal zone melting of InSb at large inertial accelerations (up to 30 times earth gravity) is reported. The experiments were carried out on a centrifuge arrangement which permits to vary the driving force of convection in a wide range. The occurrence of temperature fluctuations in the melt zone and of doping striations in the growing crystal is investigated in dependence on resulting acceleration. This is explained by unsteady convection which is discussed in relation to existing theoretical work. A suppression of unsteady convection and doping striations at large acceleration is reported which has been observed for the first time in horizontal zone melting.