1988 年 28 巻 10 号 p. 809-817
Structure change during reversion of phase-decomposed alloys has been investigated by using the kinetic Ising model (Kawasaki dynamics) on fcc lattice, and the results have been compared with the experimental results obtained by means of synchrotron radiation small-angle scattering (SR-SAXS) study of Al-Zn binary alloys. From the real-space configuration of solute atoms obtained by the simulation, the structure of the system was investigated. The structure function was also calculated by Fourier transform, in order that direct comparison with SAXS experiments was possible. It was made clear that the time evolution of the structure parameters during phase decomposition agreed qualitatively with those obtained by Lebowitz et al, for a simple cubic lattice. The structure change during reversion was found to be divided into two distinct stages: The earlier one is characterized by the rapid reduction of the composition of precipitates, with almost constant volume fraction. The later one is characterized as the stage where precipitates shrink to dissolve with almost constant composition. For reversion below the coexistence curve, the coarsening process at the reversion temperature followed the reversion process. It was found that the structure change during reversion in Al-Zn binary alloys was very similar to the one observed in the present simulation, and the further discussion based on the two phase analysis with the small-angle X-ray scattering results agreed well with the present results.
