Spatially resolved deformation studies on carbon steel employing X‐rays and positron annihilation

Abstract

Spatially resolved studies on plasticity in a polycrystalline sample of the ferritic carbon steel C45E (AISI 1045) were performed after deformation in a three-point bending test. The local effects of deformation were investigated by scanning the sample with two different methods: Positron Annihilation Spectroscopy (S-parameter) and Debye-Scherrer diffraction (reflex broadening). A simple relation between the results of both experiments and the true strain over the cross-section of the bent sample is presented in this letter. Comparing the methods a linear correlation between the lattice distortion of α-iron and the defect sensitive positron annihilation parameter is found.

Material Science with Positrons: From Doppler Spectroscopy to Failure Prediction

“…Figure 1 shows the S-parameter (a) and the broadening of the {200} reflections of the ferritic α-phase in scans over the cross-section of the bent sample. Comparing both methods, a linear correlation between the density of vacancy-like defects and dislocations was found [33]. This reflects the proportionality between the production rates of dislocations and associated vacancy-like defects during plastic deformation.…”