First of all, this is, of course, an active cold deformation (deformation, in which
the vectors of deformation loads do not change their direction in relation to the
deformable object, and the deformation stress practically constantly increases). The
parameters of the active deformation are: degree of deformation, scheme of
deformation, use of different loading schemes in a certain sequence, degree of
deformation at which the subsequent vacancy alloying gives the maximum effect. From
the noted follows the presence of a significant number of parameters of the active cold
deformation, which requires their optimization for the given object with its deformation
and obtaining properties. It is possible to use the following proven schemes of the
active cold deformation: uniaxial tension, drawing, rolling, uniform unequal
compression. In the context of the developing concept of injection the non-equilibrium
concentration of vacancies into the object, which substantially changes the mechanism
of the plastic deformation and the resulting complex of properties of the cold-worked
metal, the scheme of uniform unequal compression is particularly attractive since it
does not require specific technological operations for alloying of the object with the
non-equilibrium concentration of vacancies. Such alloying is conducted in the process
of the deformation of the object. The equilibrium concentration of vacancies at the
temperature of cold deformation becomes non-equilibrium with the increase of the
uniform pressure [4]. However, this advantage of the uniform unequal compression
scheme is largely cancelled out by the need for high energy costs and low process
performance in comparison with the deformation schemes described above [7].
Therefore, for technologies for manufacturing the cold-hardened steel products of mass
use, one should choose simpler cold deformation schemes and other methods of
alloying of the processed objects with the non-equilibrium concentration of vacancies.
In this case, it is necessary to make maximum use of the influence of the deformation
scheme of the same geometric deformation degree on the resistance to brittle failure
determined by the experiments [8, 9] and to determine the effects of the influence of
non-equilibrium concentration of vacancies on the forming dislocation structure of the
object by other and more productive methods than the uniform unequal compression.
If we take into account that manufactured objects can be exposed not only to
brittle failure, but also to ductile failure by brittle type [10], then it is important to use
the influence of the deformation scheme and the geometry of the loaded object on the
tendency to localize the plastic deformation [11].
In general, the criteria for optimizing the parameters of active deformation can be
the following: the minimization of energy costs, stored elastic energy of the object, risk
of crack formation, ductile failure by brittle type, tendency to deformation aging. The
theoretical basis for achieving this minimization by optimizing the technological
parameters of the active cold deformation, as well as the operations of alloying with
the non-equilibrium concentration of vacancies, is the following: obtaining a
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