non-equilibrium concentration of vacancies by means of one or another kind of the
vacancy hardening.
B. The technological operation of alloying with the non-equilibrium concentration
of vacancies is carried out after the technological operation of active cold deformation.
As a rule, the technological operation used here is alloying with the non-equilibrium
concentration of vacancies by the method of cyclic deformation.
C. The technological operation of alloying with the non-equilibrium concentration
of vacancies is combined with the technological operation of active cold deformation.
The method of cyclic deformation is also used here.
Most often, scheme B is used for a billet hardened by the active cold deformation
before the technological operation of active cold deformation during the formation of
the geometry of the product, and also after this technological operation, i.e. on the
product with final geometry (often in the complex of relaxation stabilizing treatment).
The use of the scheme B can be of value for a billet if it is deformed by a given
degree of deformation by fractional deformations.
In general, the technological operations of alloying with the non-equilibrium
concentration of vacancies have the following main effects:
1.
Reduction of the active cold deformation resistance.
2.
Obtaining a given dislocation substructure at lower degrees of deformation.
3.
Ensuring the necessary technological ductility to a billet hardened by the
active cold deformation for the subsequent technological active cold deformation, that
forms the geometry of the product.
4.
Forming of the structural state of the finished product with specified
properties that are sufficiently stable under various impacts during operation.
These rather particular effects listed above have been experimentally confirmed
during the active cold deformation after the vacancy hardening of the ingot iron of low-
carbon steel and austenitic steel, and have been more definite for the first objects (due
to the much higher stacking fault energy in α-Fe compared to γ-Fe). A 5-10% tensile
strain of the ingot iron in the conditions described above had led to the formation of
the dislocation substructure similar to that formed under the ordinary conditions at 30-
40% deformation. It is probable that the deformation under the conditions when
presence of the non-equilibrium concentration of vacancies in metal provided a smaller
amount of the stored elastic energy, since along with the hardening of the iron to the
yield strength value of ~700 MPa the cold brittleness temperature decreased to –60…–
70
0
С. This deformation of the normalized iron had raised the cold brittleness
temperature in comparison with the normalized state to +10…+30
0
С at a significantly
lower yield strength value of 250…300 MPa [5, 15].
With the optimization of the cold deformation scheme or the combinations of such
schemes, as well as the alloying operations with the non-equilibrium concentration of
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