Besides the tendency variation in each point, the strain mutation appears except the sample of soft inclusion, based on which the concept of strain nucleation is put forward.

It considers point, line and interfacial defects in the context of structural transformations including annealing, spinodal decomposition, nucleation, growth, and particle coarsening.

The experimental results show that the ratio of the bar-like defects to the point-like ones decreases with increase in time of nucleation annealing at a low temperature.