dislocation substructure with microvolumes minimum of piling-up of equivalent
dislocations, and with microvolumes maximum of the "geometric" interaction of
dislocations, which leads to mutual quenching of the dislocation stress pattern,
dislocation substructure, described as a regular substructure of dislocation fragments
with quasi-equilibrium dislocation boundaries. The principles of the developing
technology allow obtaining the required level of hardening in two ways: a) by the
technological deformation of an unhardened billet in the manufacture of a product of a
given geometry; b) if the preset level of hardening and a set of properties are not
achieved here, then the hardening of the billet is planned. With option b) the conditions
for optimizing the technological parameters become more complicated, since the
deformation of the billet should not only harden it, but also give it the necessary
technological ductility. In fact, the task of manufacturing a hardened product according
to the scheme "hardening of the billet – manufacturing a product using cold
deformation" requires a particular solution to the problem – to which extent the
structural state of the billet is "distorted" during the cold deformation of the product,
and how to solve the problem of optimizing the billet deformation taking into account
the subsequent deformation. Nevertheless, it is possible to use the general theoretical
basis for development of such technological process, which should solve the main issue
– manufacturing a finished cold-worked product with a given structural state and a
complex of properties. We have collected observational data for the possibility to
obtain this type of dislocation structure (sometimes in combination with a
microstructure), in which the subsequent cold deformation and the aging after it,
despite causing additional hardening, does not substantially reduce the brittle failure
resistance [12, 13].
Taking into account the importance of optimizing the technological parameters of
the active cold deformation alloying with the non-equilibrium concentration of
vacancies, it is necessary to emphasize the prospects of optimizing not only the
technological parameters of the process, but also optimizing the geometry of the
products. Here, the principles of the geometrical structural hardening can be used [14].
If the product is mostly exposed to the brittle failure, then the massiveness of the
product and the distance between its free surfaces should be reduced. If there is a risk
of the ductile failure by brittle type, then the degree of reduction in diameters,
thicknesses, etc. should be limited in products, taking into account the schemes of
operational loading and the geometry of the product.
Active cold deformation solves the problem of structural alloying of the object by
linear defects (dislocations), which is, figuratively speaking, provides the supply of
"building material" for the development of dislocation configurations. The task of the
vacancies with the necessary non-equilibrium concentration injected into the object is
to ensure the specific interaction of vacancies and dislocations (primarily the moving
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