这段话主要说明的是什么结论？

jgaus

annealing twinning is promoted by high velocity grain boundary migration, which
can be induced by (1) the grain boundary curvature that decreases when grain size increases (2)dislocation density gradients that are produced by low deformation steps applied at high strain rates and can sustain high velocity grain boundary migration even when grain size increases. The driving force related to curvature depends also on grain size distributions, which have been identified as an important microstructure parameter. When grain boundaries migrate as a result of the driving force related to dislocation density gradients they can pass the primary precipitates despite the zener drag these precipitates exert on grain boundaries in the two-phase microstructures: those that have not undergone any supersolvus heat treatment. The dynamic recrystallization occurrence or nonoccurrence during deformation steps has also an important impact on microstructure evolution during subsequent sub- or supersolvus heat treatments.

della2012

句子好长啊