scholarly journals Impact of local technological concentrators of stresses upon operation properties of parts worked

2017 ◽  
Vol 2 (5) ◽  
pp. 31-37
Author(s):  
Сергей Никитин ◽  
Sergey Nikitin ◽  
Владимир Макаров ◽  
Vladimir Makarov ◽  
Михаил Песин ◽  
...  
Keyword(s):  
Crack Formation ◽  
Fatigue Cracks ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Local Surface ◽  
Surface Machining ◽  
Gear Teeth ◽  
Conjugate Surfaces ◽  
Complex Profile Surfaces ◽  
Transition Areas

It is defined that during the machining of complex surfaces in parts operating under large fluctuating loads, in critical transition areas of profile conjugate surfaces there are formed local technological concentrators of stresses contributing to formation, development of fatigue cracks and to further destruction of parts in the course of operation. Such phenomena are discovered, for instance, at high-loaded gear teeth machining, at turbine blade profile surface machining, at manufacturing large-modular tapered threads and other parts having complex profile surfaces. There are developed and introduced methods for value decrease of such stress concentrators on the basis of the application of different methods for local surface plastic deformation of a surface layer in transition areas of profiles. As a result the probability of fatigue crack formation decreased considerably and fatigue strength in parts machined increased essentially.

scholarly journals Use of different methods of local SPD (surface plastic deformation) to reduce stress concentrator impact upon profile surfaces of transport machinery parts

2019 ◽  
Vol 2019 (7) ◽  
pp. 42-48
Author(s):  
Владимир Макаров ◽  
Vladimir Makarov ◽  
Александр Горбунов ◽  
Alexander Gorbunov
Keyword(s):  
Plastic Deformation ◽  
Stress Concentrator ◽  
Fatigue Cracks ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Local Surface ◽  
Complex Profile ◽  
Stress Concentrators ◽  
Transition Areas ◽  
Technological Stress

It is defined that in the course of machining complex profile parts operating under heavy alternating loads, in critical transition areas of profile conjugated surfaces there are formed local technological stress concentrators promoting the formation and growth of fatigue cracks and further destruction of operating parts. There are developed and introduced methods to reduce the values of such stress concentrators on the basis of the application of different methods of local surface plastic deformation.

Influence of the deforming tool kinematics on the stress state of the surface layer during hardening of cylindrical parts

2021 ◽  
pp. 28-32
Author(s):  
Keyword(s):  
Plastic Deformation ◽  
Surface Layer ◽  
Stress State ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
The Finite Element Method ◽  
Kinematic Scheme ◽  
Local Surface ◽  
Hardening Process ◽  
Cylindrical Parts

The influence of kinematic schemes of processing by local surface plastic deformation on the intensification of the stressed state of cylindrical surfaces of parts is considered. On the basis of the finite element method by computer simulation, a mathematical model of the hardening process was obtained to determine the stress state in the surface layer for different hardening schemes. Keywords: kinematic scheme of processing, deforming tool, orbital burnishing, intensification of the stress state, residual stresses, depth of plastic deformation. [email protected], [email protected]

Effect of surface plastic deformation on the development of fatigue cracks

1974 ◽  
Vol 6 (1) ◽  
pp. 93-95
Author(s):  
M. A. Balter ◽  
L. Ya. Gol'dshtein ◽  
A. A. Chernyakova ◽  
A. I. Reznik
Keyword(s):  
Plastic Deformation ◽  
Fatigue Cracks ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Effect Of Surface

scholarly journals Influence of reinforcing plastic surface deformation on surface performance of machine parts

2019 ◽  
pp. 7-14
Author(s):  
Z. М. Оdosii ◽  
V. Ya. Shymanskyi ◽  
B. V. Pindra
Keyword(s):  
Plastic Deformation ◽  
Surface Layer ◽  
Residual Stresses ◽  
Surface Deformation ◽  
Fatigue Cracks ◽  
Surface Plastic Deformation ◽  
Original Structure ◽  
Physical Parameters ◽  
Surface Plastic ◽  
Machine Parts

The performance of the machines part reinforcement using surface plastic deformation shall be considered as formation of the whole complex of surface parameters and quality and their impact on the operational properties of these parts. The main surface quality parameters, affecting the performance of machine parts are geometric (microgeometry, wavelength, roughness, shape of inequalities, the size of the supporting surface, the direction of the traces of processing); physical parameters (structure, degree and slander depth, residual stresses in the surface layer). In the machine building, many methods of superficial plastic deformation are used for part reinforcement; these methods essentially differ in the scheme of impact of the surface deforming part to be treated. After analyzing the results obtained by scientists, involved in research on surface plastic deformation of surface layers and surfaces of parts, it was found that after hardening, practically all structural changes contribute to reinforcement of the surface layer material and increase the plastic deformation resistance. Increasing the density of dislocations and the separation of carbides, which block the shear slides and create obstacles to the movement of dislocations. Due to these changes, resistance to formation and spread of fatigue cracks have increased. The treatment depth, magnitude of residual stresses and increase in hardness depends on the original structure and chemical composition of the material. Reinforcement regimes have significant effects on the wear resistance. Use  of diamond smoothing, vibration processing, combined methods (surface plastic deformation in combination with other reinforcement methods, as well as the use of a combined tool) opens up new possibilities for increasing the quality characteristics of the surface and the surface layer of parts, and accordingly, increasing their operational properties with all the diversity and complexity of used processes. Based on the results of the studies, practical recommendations on the application of methods of hardening by surface plastic deformation of machine parts and a methodology for designing technological processes for their manufacture considering manufacturing capabilities are proposed.

SELECTION OF THE DRIVE OF THE PULSE GENERATOR FOR WAVE DEFORMATION HARDENING

2020 ◽  
Author(s):  
Andrey Kirichek ◽  
Dmitriy Solovyev
Keyword(s):  
Strain Hardening ◽  
Pulse Generator ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Impact Frequency ◽  
Metal Consumption ◽  
Pulse Generators ◽  
Energy Impact ◽  
Deformation Hardening ◽  
Selection Of

The article is devoted to the analysis of known structures of impact devices used in industry in order to obtain recommendations for their adaptation or when creating new structures for wave strain hardening by surface plastic deformation. The analysis was carried out on the used drive and on the main parameters of impact devices: impact energy, impact frequency, relative metal consumption and efficiency. The options are the best combinations of parameters for electric, pneumatic and hydraulic drives. Recommendations are given on the use of such devices, with appropriate adaptation, as pulse generators for wave strain hardening.

New methods for surface plastic deformation of low-rigidity cylindrical machine parts

2018 ◽  
Vol 2018 (8) ◽  
pp. 16-24 ◽  
Author(s):  
Семен Зайдес ◽  
Semen Zaides
Keyword(s):  
Plastic Deformation ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
High Productivity ◽  
Surface Strengthening ◽  
New Methods ◽  
Machine Parts

Technological potentialities at finish-strengthening processing of low-rigid parts of shaft- and axle types with local ways of machining impact are rather limited. In the paper there are considered new ways for strengthening allowing obtaining qualitative surface strengthening in machine parts at high productivity of an engineering procedure.

Plastic deformation of collector plates at electric motor repair

2020 ◽  
pp. 79-82
Author(s):  
D.YU. Belan ◽  
G.B. Toder ◽  
K.V. Averkov ◽  
YU.V. Titov
Keyword(s):  
Plastic Deformation ◽  
Electric Motor ◽  
Roughness Parameter ◽  
Surface Plastic Deformation ◽  
Analytical Dependence ◽  
Surface Plastic ◽  
Machined Surface ◽  
Tool Surface ◽  
Diamond Burnishing ◽  
Traction Electric Motor

A tool was developed for smoothing the plates of an electric motor collector. An analytical dependence of the roughness parameter of the machined surface on the force applied to the tool is obtained. Keywords traction electric motor, collector, diamond burnishing tool, surface-plastic deformation, repair, roughness. [email protected]

A Neutron Diffraction Investigation of Residual Stresses in Rail Ends after Severe Deformation of Rail Surfaces

2014 ◽  
Vol 777 ◽  
pp. 213-218 ◽  
Author(s):  
Chandrahas Rathod ◽  
David Wexler ◽  
Vladimir Luzin ◽  
Paul Boyd ◽  
Manicka Dhanasekar
Keyword(s):  
Neutron Diffraction ◽  
Residual Stresses ◽  
Vertical Plane ◽  
Surface Plastic Deformation ◽  
Primary Component ◽  
Rolling Contact ◽  
Surface Plastic ◽  
Stress Evolution ◽  
Test Rig ◽  
Complex Deformation

Insulated rail joints (IRJs) are a primary component of the rail track safety and signalling systems. Rails are supported by two fishplates which are fastened by bolts and nuts and, with the support of sleepers and track ballast, form an integrated assembly. IRJ failure can result from progressive defects, the propagation of which is influenced by residual stresses in the rail. Residual stresses change significantly during service due to the complex deformation and damage effects associated with wheel rolling, sliding and impact. IRJ failures can occur when metal flows over the insulated rail gap (typically 6-8 mm width), breaks the electrically isolated section of track and results in malfunction of the track signalling system. In this investigation, residual stress measurements were obtained from rail-ends which had undergone controlled amounts of surface plastic deformation using a full scale wheel-on-track simulation test rig. Results were compared with those obtained from similar investigations performed on rail ends associated with ex-service IRJs. Residual stresses were measured by neutron diffraction at the Australian Nuclear Science and Technology Organisation (ANSTO). Measurements with constant gauge volume 3x3x3 mm3 were carried in the central vertical plane on 5mm thick sliced rail samples cut by an electric discharge machine (EDM). Stress evolution at the rail ends was found to exhibit characteristics similar to those of the ex-service rails, with a compressive zone of 5mm deep that is counterbalanced by a tension zone beneath, extending to a depth of around 15mm. However, in contrast to the ex-service rails, the type of stress distribution in the test-rig deformed samples was apparently different due to the localization of load under the particular test conditions. In the latter, in contrast with clear stress evolution, there was no obvious evolution of d0. Since d0 reflects rather long-term accumulation of crystal lattice damage and microstructural changes due to service load, the loading history of the test rig samples has not reached the same level as the ex-service rails. It is concluded that the wheel-on-rail simulation rig provides the potential capability for testing the wheel-rail rolling contact conditions in rails, rail ends and insulated rail joints.

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