Scientific progress volume ǀ issue ǀ

ǀ
ISSUE 2 
ǀ
2022 
ISSN: 2181-1601
Uzbekistan
 
www.scientificprogress.uz
 
Page 685
lower roughness with a favorable microroughness shape, and compared to some impact 
processing methods, static methods allow achieving a greater degree of hardening [1]. 
As working bodies, deforming elements of various configurations and sizes, balls, 
shot, deforming elements, the working surface of which is a body of revolution, are 
used. PPD can be performed simultaneously by several processing methods (combined 
PAP) or sequentially by several methods (combined PAP). 
The prospects for the development of SPD are due to the following features and 
advantages of this type of processing: the preservation of the initial volume of metal 
during shaping processes ensures its significant savings; preservation of the integrity of 
metal fibers, hardening of its surface layer, accompanying cold plastic deformation, 
creation of significant compressive residual stresses during shaping, finishing and, 
especially, hardening processing. 
METHODS 
The study of the elastoplastic deformation process involves, at the first stage, the 
establishment of the geometric parameters of the contact zone, since the physical and 
mechanical processes and the qualitative transformation of the surface layer occur 
within it. As a rule, when studying the geometric parameters of the contact zone, one 
parameter is determined - the contact area, assuming that it is the dominant indicator 
that determines the results of PPD processing. 
Let us further agree to consider any body of revolution as a deforming element; in 
a particular case, a specified deforming element will be called a roller for simplicity. 
The contact between the deforming element and the part, in addition to the contact 
area, is characterized by other parameters. These include: change in the half-width of 
the contact along its length (the equation of the contact contour line), the maximum 
half-width and length of the contact, the change in the depth of penetration of the 
deforming element along the line of its maximum loading, the volume of metal 
displaced from under the deforming element, the surface area of the contact (the area of 
the part deforming element in contact with the surface of the part). 
These geometric parameters determine the nature of the distribution of strains and 
stresses over the contact area, the deformation force, and directly depend on the 
geometric parameters of the deforming elements, the dimensions and type of the surface 
of the part (shaft, hole, plane), the mechanical properties of the metal being machined, 
and the depth of penetration of the deforming element into the machined surface. 
The determination of the geometrical parameters of the contact zone during SPD in 
the vast majority of calculated dependencies refers to deforming elements that have the 
simplest shape of the working surface: a ball, a torus, a cylinder, a right circular cone, or 
a combination of these surfaces. The shape of the contact in these cases is an ellipse or 
rectangle. When determining the geometry of the contact, there is no methodological 

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