Localization of plastic deformation of quenched structural steel

Abstract

Beginning with the study of Luders bands, researchers have paid enormous attention to plastic deformation processes [1, 2]. At the micro level, the goal of such research is to find a unique relation between the parameters of the dislocation structure and the deformation of metal [3]. The evolution of the dislocation structure on deformation does not reduce to simple increase in dislocation density but is a very complex process in which spatially inhomogeneous defect distributions are created. At high degrees of deformation, when the inhomogeneity of the plastic deformation is most pronounced, nondislocational deformation channels may appear [4]. In intense plastic deformation of 08 E 2C steel (ferritic‐pearlitic state) by drawing at room temperature, extended regions with ultradisperse structure—deformation channels—may be formed, as shown in [5‐7]. Such regions are seen as mottled contrast on dark-field images in matrix reflexes. Electron-microdiffraction patterns of the surfaces of such regions have a quasiannular structure as a rule. The deformation channels are sites of localization of the deformation. The length of such regions is tens of microns; their width is 1 μ m. With increase in the degree of deformation, the mean dimensions of the deformation channels increase [5‐7].