Deformation mechanisms in a nanocrystalline vitroperm alloy

In the current investigation, microstructures with different grain sizes in the nanorange were obtained in an initially amorphous Fe-based alloy by controlling annealing parameters. The as-annealed samples revealed microstructures of varying morphology, and these different states were tested in tension in a wide range of temperatures and strain rates. The microstuctural information and the mechanical data obtained from these tests were analyzed in the context of plasticity at diminished length scales. Special emphasis is given to the difficulty of intragranular dislocation generation inside the matrix in truly nanoscale structures and its implication to affect slip accommodation processes in current models of nanocrystalline plasticity at elevated temperatures.