抄録
It is considered that the free energy of the microstructure ought to be evaluated as the set of many precipitate particles. In the present work, a new method to estimate the total free energy of the microstructure containing a chemical free energy, an elastic strain energy, an interfacial energy and so on was proposed, and then a possibility of prediction to the microstructure development was discussed on the basis of the free energy evaluated. The results obtained are as follows: (1) The interfacial energy of the microstructure vaties in parabola with the volume fraction of precipitates f. (2) The sequence of microstructure development during ageing can be predicted by comprehensive evaluations on the free energies of the various modes of microstructure.