Structure-Phase Transformations in the Quenched Constructional Steel at Deformation

Abstract

The process of plastic deformation of quenched constructional 38CrNi3MoV (0.38% C, < 1% Cr, 3% Ni, < 1% Mo, < 1% V) steel is studied by methods of transmission electron diffraction microscopy and X-ray structure analysis. The stages of deformation curves are revealed during the steel compression. Deformation localization places, namely, deformation channels having the transverse size of 0.5 μm and longitudinal ones of some microns, are revealed and analysed. In deformation channels, there are fragments with sizes of 50–100 nm. Longitudinal fragment sizes of martensite crystals are decreased, and microtwins’ density, scalar and excess dislocation density, amplitude of long-range stress fields are increased with the deformation-degree growth. The possible places of carbon-atoms localization in the steel structure are determined. As shown, the total quantity of carbon atoms located in the solid solutions based on α- or γ-Fe is increased, and it is decreased on the structure defects with the growth of deformation degree.

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