Physical, microstructural and mechanical study of isochronal annealing of deformed commercial iron

Abstract

Isochronal annealing of deformed commercial iron samples (99.88 m.-% Fe) after cold deformation is studied by means of Vickers microhardness and physical techniques based on positron annihilation (positron annihilation lifetime spectroscopy (PALS) and Doppler broadening of the annihilation radiation (DBAR)). Undeformed Fe with a purity of 99.998 m.-% was used as a reference material to compare it with the used commercial Fe. Additionally, EBSD (electron backscatterded diffraction) was used to estimate the recrystallization fraction in the samples. In the temperature range 600–1000 °C the recrystallization phenomenon can be followed with these techniques and similar results are obtained, while in the temperature range 20–600 °C the recovery process has to be included and the results for positron annihilation lifetime presented a deviation due to its sensitiveness for changes in point defect configurations.