ones). This stimulates the non-conservative sliding of dislocations and certain changes
in their geometry. Eventually, it is ensured that the quasi-equilibrium dislocation
configurations are obtained with the maximum possible "mutual quenching" effect of
the stress pattern in dislocations. The second main type of the technological operations
in the developing technology are technological operations of the vacancy alloying of
the object, which differ by: the used type (mechanism) of this alloying; the place in the
technological process in relation to the technological operation – active cold
deformation, as well as by the mechanism for obtaining the non-equilibrium
concentration of vacancies.
A more detailed consideration is necessary for the technological operations
associated with object alloying with the non-equilibrium concentration of vacancies,
since they are characterized to the maximum degree by novelty and provide a number
of unusual effects in the technological chain. This project offers several methods for
manufacturing and alloying with the non-equilibrium concentration of vacancies.
Conditionally they can be divided into 2 types. 1. Thermal action – means vacancy
hardening, based on the temperature dependence of the equilibrium concentration and
the possibility of fixing an increased concentration of vacancies at temperatures of the
active cold deformation by sufficiently rapid cooling. The need for high-temperature
heating and rapid cooling is a technological disadvantage of the vacancy hardening
method. Calculations and experiments determine the necessary heating temperatures
and cooling rates, as well as the maximum possible time interval between the end of
quenching and the start of the active cold deformation [5, 15]: heating temperature,
cooling rate, specified time interval – these are the technological parameters of the
technological operation – vacancy hardening, with that, equalizing at the heating
temperature is not necessary. Since during the induction heating and rapid subsequent
cooling the duration of the operation is within the order of seconds, the present
technological operation does not limit the overall productivity of the technological
process. At the same time, the high heating temperatures (according to our data, 950
0
С for ingot iron and ~1200
0
С for austenitic steel [5, 15]) increase the high-temperature
cooling interval, and thereby the "annealability of the vacancies". This increases the
requirements for cooling intensity. However, the heating temperature can be
significantly reduced, relying on the data of the work [16].
Therefore, the project offers a new variant of the vacancy hardening, when the
effect of metal enrichment with vacancies is used in the process of recrystallization of
a heavily cold-worked metal. For this, a cold-worked object is subjected to high-speed
heating and, accordingly, high-speed recrystallization. In addition to the required lower
heating temperatures and cooling rates, the new variant of the vacancy hardening
makes it possible to obtain very fine grain. The latter is very favourable for the
properties of the steel products hardened by the cold deformation.
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