Thus, the technological operation of alloying of an object with the non-
equilibrium concentration of vacancies by the method of vacancy hardening can be
performed in 2 variants, differing from each other both in the initial structural state of
the object, and the sub-operations in the mentioned above technological operation. In
addition, the technological parameters such as heating temperature and cooling rate
also differ.
In the first variant, the treated object has a structural state characteristic of hot-
worked low-carbon steel, heating temperature of 900-950
0
С and higher. Cooling rates
from 10
2
dps and higher; the structural state of the steel changes due to the increase in
the non-equilibrium concentration of vacancies, it affects the mechanism of the
subsequent active cold deformation, and the forming dislocation substructure.
In the second variant, the treated object undergoes intense cold deformation prior
to heating, and its structural state is characterized by an increased density of
dislocations. The temperatures of heating for quenching are much lower than in the
first variant: for example, for steel – 600-650
0
С and lower; cooling rate under 10
2
dps.
The structural state changes both at the level of the microstructure (grain refinement),
and at the level of the crystal structure defects due to an increase in the non-equilibrium
concentration of vacancies. Such structural state affects the mechanism of the
subsequent active cold deformation and the forming dislocation substructure not only
due to the non-equilibrium concentration of vacancies, but also due to the substantial
reduction in the grain size.
Common to these analyzed variants is the need for the high-speed heating and
cooling, as well as the ordering of values of the time interval between the end of cooling
and the start of the active cold deformation.
2. The second method of the object alloying with the non-equilibrium
concentration of vacancies consists in performing a deformation action by cyclic
deformation based on an increase in the values of the non-equilibrium concentration of
vacancies due to the peculiar properties of the dislocation mechanism of the cyclic
deformation. It is possible to use both methods in one technological flow, depending
on the structural state of the object, its technological form (billet or product) and the
expected effect.
The technological parameters of the used types of cyclic deformation are: loading
scheme, amplitude, frequency and number of cycles. The important feature is the time
tie between the technological operation of the active cold deformation and the
technological operation of alloying with the non-equilibrium concentration of
vacancies. This project provides the following options for the above-mentioned tie:
A. The technological operation of alloying with the non-equilibrium
concentration of vacancies is preceded by the technological operation – active cold
deformation, realized with the use of the technological operation of alloying with the
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