Isochronal annealing studies of deformed FeSi alloys using positron annihilation spectroscopy

A series of FeSi samples were deformed to a thickness reduction of 16%. They were isochronally annealed for one hour at different temperatures and characterized by the Doppler broadening of the annihilation radiation (DBAR) measured at room temperature. Optical microscopy (OM) is used to investigate the microstructure of the deformed samples before and after annealing. The SS parameter data show a decrease with the increase of the annealing temperature. At 973 K a significant decrease sets in. The microstructures of the alloys, investigated by OM, show that recrystallization is completed at 1173 K.

► Cold deformation of FeSi leads to the creation of dislocations.
► Annealing of the FeSi alloys leads to a decrease of the concentration of defects.
► The FeSi alloys became nearly free of defects after the annealing at 1173 K.
► PAS is proved to be a sensitive technique of detecting defects.