Scientific progress volume ǀ issue ǀ

ǀ
ISSUE 2 
ǀ
2022 
ISSN: 2181-1601
Uzbekistan
 
www.scientificprogress.uz
 
Page 684
The scientific results achieved so far make it possible in many cases to reasonably 
assign processing modes and make a choice of rational design parameters of the 
processing deforming tool. However, in view of the complexity of the RPM process and 
a large number of factors that affect the productivity of the quality of the machined 
surface, there are difficulties in choosing their optimal combination, and in some cases 
there are conflicting information that does not allow unambiguously assessing the 
degree of influence of certain processing parameters on the RPM process. . 
The transformation of the qualitative state of the surface of the part is carried out as 
a result of plastic deformation, which consists in the irreversible forced movement of 
individual atoms or their groups, is a complex process, the study and management of 
which is complicated by the following factors: 
• Without exception, all metals are alloys containing soluble or insoluble impurities
in varying amounts and are characterized by a heterogeneous structure. 
• The complexity of studying the processes of plastic deformation of a metal is due 
to the fact that, for given initial mechanical properties, the value of the resistance of the 
metal to plastic deformation is continuously changing, since at the same time there are 
changes in the mechanical properties of the surface layer caused by hardening. These 
changes are heterogeneous in nature. Therefore, when calculating the parameters of 
metal treatment modes by pressure, it is necessary to first experimentally establish a 
functional dependence characteristic of a given metal, which relates its resistance to 
plastic deformation with the amount of deformation. 
• 
The phenomena that characterize the process of plastic deformation are 
determined by the structure and properties of the metal being processed. 
• All metals have a polycrystalline structure, i.e. they are a set of soldered 
crystallites-grains of irregular shape, anisotropic in mechanical, chemical and physical 
properties. 
• The mechanism of cold and hot plastic deformation is different. Cold 
deformation is characterized by shear deformation and bending of the spatial lattice. 
Processes such as diffusion plastic deformation and recrystallization, which are 
characteristic of hot deformation, are practically absent during cold deformation. 
• During surface plastic deformation, only the surface layer of the part material is 
plastically deformed. 
There are static, shock, vibration and ultrasonic 1111D 72]. With static methods, 
the tool, working fluid or medium acts on the surface to be treated with a certain 
constant force, while there is a smooth and consistent movement of the focus of 
influence over the entire surface. With impact methods, the tool or working bodies 
repeatedly and consistently act on its entire part, while the impact force each time 
changes from zero to a certain maximum value. Static SPD methods, as a rule, provide a 

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SCIENTIFIC PROGRESS
VOLUME 3