Scientific progress volume ǀ issue ǀ

ǀ
ISSUE 2 
ǀ
2022 
ISSN: 2181-1601
Uzbekistan
 
www.scientificprogress.uz
 
Page 688
of the half-width of the contact along its length, the problem is reduced mainly to 
finding the contour line limiting the contact. 
Determining the relationship between the geometric parameters of the deforming 
elements and the geometric parameters of the contact zone can be solved on the basis of 
direct and inverse problems. 
When solving the direct problem, the initial data are the geometric parameters of 
the deforming element (maximum diameter and length, as well as the equation for 
changing the radius along the length of the contact that determines its shape), the depth 
of penetration into the machined surface, the dimensions and type of the part (hole, shaft 
or plane) , after which the geometric parameters of the contact are determined. 
When solving the inverse problem, the shape and dimensions of the contact zone 
are specified, and then the geometric parameters of the deforming element are 
determined, which provide a given contact located on the surface of a part of a given 
type and size. When studying the SPD process, most authors use the solution of the 
direct problem [4]. The importance of the inverse problem lies in the fact that, first, the 
necessary rational shape and dimensions of the contact zone can be set, at which the 
required stress distribution over the contact area and quality indicators of the surface 
layer are achieved, and then, based on these data, the transition to the choice of design 
parameters of the deforming element and technological parameters is carried out. PPD 
modes. In addition, some questions can be more simply and rationally solved only on 
the basis of an inverse problem. For example, by setting a contact zone of the same size 
and shape, it is possible to investigate the influence of the shape and size of the 
deforming elements, the size and type of the treated surface on the deformation force 
and the quality of the surface layer. 
One of the issues to be solved when determining the parameters of the contact zone 
is related to the identification of a correspondence between a static imprint with a 
simple indentation of a deforming element and an imprint that occurs when the 
deforming element rolls along an elastically deformable surface. Obviously, the 
conditions for the formation of the contact zone in both cases are somewhat different. 
This relationship cannot be established through the development of an appropriate 
mathematical model. However, it should be borne in mind that the chipping process is 
classified as a static process. This means that practically on the entire processing 
interval, with the exception of the initial short-term and final time intervals, the 
processing is stationary. Therefore, we can assume the constancy of the contact 
parameters over the entire period of processing time, and when developing 
dependencies for determining the parameters of the contact zone, consider the contact 
instantaneous and embedded in the part as with static indentation. The difference 
between contacts during static indentation and rolling of the roller on the machined 

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SCIENTIFIC PROGRESS
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