fragmented substructure, in its turn, contains either the chaotically spreaded dislocations or the 
lattices. 
The interesting peculiarity of dislocation structure of steel being investigated is the presence of a I 
large number of dislocation loops of the vacant type in initial state. As a rule, the loops are in grains 
with chaotic dislocation substructure. x 
The researches of the phase composition of steel have found out the following: In material as a © 
result of preliminary treatment in initial state the particles of a complex carbide of M3Cs- 
(FeCr)»3Cs type and titanium carbide of the TiC composition have been formed. The particles of I 
M,3;C¢ carbide are in inside and at boundaries of grains and have the form of spheroid. The particles ie 
of TiC carbide generally are in inside of a grains, i.e. on dislocations and subboundaries (boundaries ui 
of fragments) they have the rounded form. It is stated, that the particles of M3Cs carbide are coarser 
than the particles of TiC carbide, however the volumetric part of them is lower. The medium sizes 
of carbide particles located in lines are 1,3 microns, but the particles located at the boundaries of 
grains are 6,5 microns. 
It is shown by metallographic investigations that the electrostimulation plastically not changing the 
form of grains increases their medium size in surface layer of steel bringing in to a value of 26 
mem. The growth of grains is accompanied by change of their distribution according to sizes: 
practically the grains disappear fully, the sizes of which are less than 10 mem. The change of } 
function of distribution the grains according to sizes testify that during the process of i 
electrostimulation in a medium being analized probably the collecting recrystallization runs. 
However, this process is of incompleted character. The boundaries of grains in many cases are 
corrected that indicates their unbalanced state. 
In initial state many grains contain twins of annealing. The volume fraction of such grains is ~0,28 n 
of material structure. The electrostimulation is accompanied by intensive twinning of steel. The ) 
volume fraction of grains with twins is increased up to ~0,7. Here, both the increase of medium 
sizes of twins and the amounts of grains containing the twins are marked. Hence, the 
electrostimulation promotes to twinning of steel by the growth of old and formation of new twins. 
The electrostimulation of initial sample brings to some reconstruction of dislocation substructure: 
the volume fraction of substructure of dislocation chaos (appiox, up to 60%) is lowered and the 
volume fraction of grid — and cell — substructure is increased. respectively. 
The ordering of dislocation substructure during electrostimulation is accompanied by some changes 
of the value of dislocation density. Namely: the density of dislocations in grid-substructure located 
in grains, is lowered, but in grid-substructure, located in fragments it is increased. The density of 
dislocations in a structure of dislocation chaos is not practically changed. Here, the value of scalar 
density of dislocations in average by material in current action is increased slightly from 2.3x10° 
cm’? in initial state to 3,3x10° cm. 
This difference becomes the most essential in areas of material adjoining the surface of failure. 
Namely: the electrostimulated sample is broken down at higher values of scalar density of 
dislocations and density of curved extinction contoures, small number of microcracks and value of 
torsion curvature of the crystalline lattice in comparison with initial sample. The dislocation 
substructure in area of material adjoining the surface of failure of the initial and electrostimulated 
samples evolutionizes in some different way. As it follows from the results. the electrostimulating 
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