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.

TECHNOLOGY OF COMBINED ELECTROMECHANOULTRASONIC TREATMENT OF SURFACE LAYERS OF MACHINE PARTS

2020 ◽  
Vol 2 ◽  
pp. 26-33
Author(s):  
V.R. EDIGAROV
Keyword(s):  
Plastic Deformation ◽  
Surface Layer ◽  
Residual Stresses ◽  
Ultrasonic Treatment ◽  
Mechanical Treatment ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Surface Layers ◽  
Machine Parts ◽  
Acoustic Treatment

The technology of combined electro–mechanical–acoustic treatment is presented, which is a combination of electro–mechanical treatment and surface plastic deformation by ultrasonic treatment. Microhardness and residual stresses in strengthened EMUzO surface layer of machine parts investigated.

scholarly journals Quality improvement of calibrated steel by surface deformation. Part 1. Determination of the stressed state of cylinderical parts during orbital surface deformation

2020 ◽  
Vol 63 (10) ◽  
pp. 802-807
Author(s):  
S. A. Zaides ◽  
. Pham Van Anh
Keyword(s):  
Surface Layer ◽  
Residual Stresses ◽  
Deformation Zone ◽  
Surface Deformation ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Machining Performance ◽  
Cylindrical Parts ◽  
Practice Methods ◽  
Hot Rolled

Cold drawn calibrated steel is an effective blank for the manufacture of low-rigid cylindrical parts such as shafts and axles. High accuracy of the diametric size along the length of the workpiece, low surface roughness, increased hardness and strength of the surface layer compared to hot rolled products allow us to produce a variety of parts with high metal utilization and high machining performance. The main disadvantage of calibrated metal is the residual stresses that occur during pressure treatment. To reduce or change the nature of the distribution over the cross section, it is proposed to use small plastic deformations in the surface layer of the hire. Known in practice methods of surface plastic deformation (PPD) usually lead to the curvature of non-rigid workpieces. To intensify the stress-strain state in the deformation zone, we propose a method of orbital surface deformation. Based on the finite element modeling, influence of the main parameters of orbital surface deformation on stress state in the deformation zone and residual stresses in the finished products is considered. Compared with the traditional PPD process, the stress intensity during orbital surface deformation will increase by 10 – 15 %. The residual compressive stresses that form in the surface layers reach 70 – 85 % of the material tensile strength. In the second part of the article, it is supposed to provide information on a more effective method of surface deformation and on the change in initial residual stresses that are formed during the calibration of cylindrical rods.

scholarly journals Simulation and Calculation of Residual Stresses in Mining Machines Components

2018 ◽  
Vol 41 ◽  
pp. 03012 ◽  
Author(s):  
Valeriy Blumenstein ◽  
Maksim Mahalov ◽  
Oleg Ostanin
Keyword(s):  
Residual Stresses ◽  
Physical Nature ◽  
Surface Plastic Deformation ◽  
Mining Machine ◽  
Physical Parameters ◽  
Surface Plastic ◽  
Machining Processes ◽  
Hardening Treatment ◽  
Machine Parts ◽  
Express Methods

Technologies of surface plastic deformation (SPD) provide a hardening effect and create compressive residual stresses in the surface layer of mining machine parts. This leads to a significant increase in the limit of endurance and fatigue cyclic life, increases the life in fretting conditions, improves the quality of assembly joints fit, etc. Very complex are both the physical nature of the occurrence and the estimation of residual stresses, since the machining processes are related to complex nonmonotonic types of loading. The study shows the relevance of the development of computational methods for determining residual stresses in the processes of hardening treatment of critical surfaces of mining machine parts. At the same time, the design and development of experimental nondestructive express methods based on the determination of various physical parameters (acoustic, magnetic noise, coercive force, etc.) are relevant and promising. A model of the process is developed and numerical calculations of the residual stresses arising during the SPD treatment are carried out. The results of the calculations are in good agreement with the experimental data.

scholarly journals HETEROGENEOUS HARDENING OF MACHINES PARTS BY SURFACE PLASTIC DEFORMATION

2019 ◽  
pp. 106-112
Author(s):  
А. Афонин ◽  
A. Afonin ◽  
Е. Мартынов ◽  
E. Martynov ◽  
А.В. Макаров ◽  
...  
Keyword(s):  
Plastic Deformation ◽  
Surface Layer ◽  
Fatigue Loading ◽  
Hardened Layer ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Heterogeneous Structure ◽  
The Finite Element Method ◽  
Operational Characteristics ◽  
Machine Parts

The main causes of failure of heavily loaded threads are considered. The methods of increasing the efficiency of the equipment due to the method used are proposed. It is found that improving the operational characteristics of the components of mining and metallurgical machinery can be achieved forming heterogeneous-hardened surface layer. Methods of forming heterogeneous structure by surface plastic deformation (SPD are considered). The importance of identifying the nature of the influence of parameters of heterogeneous hardened layer on the performance of machine parts is indicated. Modeling of process heterogeneous hardening of SPD of the finite element method is executed. Recommendations about application of heterogeneous hardening of SPD for hardening the heavy-duty parts are offered. It is found that the use of different methods SPD allows widely vary the degree of depth and the uniformity of the hardening of machine parts. It is found that this increase in life responsible highly loaded parts operating under fatigue loading due to hardening of the heterogeneous surface layer may reach 1.5 times or more.

scholarly journals Quality improvement of calibrated steelby surface deformation. Part 2. Effect of enveloping surface deformation on residual stresses in cylindrical bars

2021 ◽  
Vol 64 (5) ◽  
pp. 330-336
Author(s):  
S. A. Zaides ◽  
Van Anh Pham ◽  
L. G. Klimova
Keyword(s):  
Residual Stress ◽  
Plastic Deformation ◽  
Residual Stresses ◽  
Surface Deformation ◽  
High Surface ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Surface Layers ◽  
Tensile Stresses ◽  
Enveloping Surface

Cold-drawn metal has a number of undeniable advantages over the hot-rolled one. Increased hardness, high surface quality, stability of the diametrical dimension along the length of the workpiece are the basis for choosing calibrated metal as effective workpieces for the manufacture of long parts such as shafts, axles, and rods. In some cases, such workpieces require a small amount of machining, for example, threading or making necks at the ends of a bar. The wider use of the calibrated metal is hindered by residual stresses that are formed during its manufacture. In the first part of this article, it was proposed to use small plastic deformations to control residual stresses. By the example of a new process of surface plastic deformation, which is called orbital burnishing, the working and residual stresses in cylindrical workpieces are determined. In the second part of the article, the process of enveloping surface plastic deformation is considered, which, at high productivity, makes it possible to reduce the residual tensile stresses in the calibrated metal or form the surface layers of the workpiece compressive stress. A technique for the experimental determination of residual stresses in the volume of a body is based on layer-by-layer removal of the inner and outer layers of cylindrical samples. Influence of the main parameters of the enveloping deformation process on the components of the residual stress tensor is established. A range of relative compressions (0.1 – 1.0 %) is revealed, at which residual compressive stresses are formed in the surface layers of the workpiece. It was found that at a relative compression of 0.5 %, the maximum residual compression stresses are created. Enveloping surface deformation has a positive effect on the residual stress state and on colddrawn metal – the residual tensile stresses can be reduced, removed or converted into compressive ones.

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.

Device for Wood-Cutting Tool Hardening

2021 ◽  
pp. 134-141
Author(s):  
Anatoly M. Buglaev ◽  
Keyword(s):  
Plastic Deformation ◽  
Surface Quality ◽  
Cutting Tool ◽  
Cutting Tools ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Labour Intensity ◽  
Machine Parts ◽  
Wood Cutting ◽  
Electrospark Hardening

Choosing effective methods and devices for surface hardening of wood-cutting tools is problematic due to the variety of their designs and operating conditions. In this regard, the development of such devices becomes an urgent task. According to the literature, one of the effective methods for increasing the service life of machine parts and tools is electrospark hardening or electrospark alloying. Industrial electrospark installations such as “EFI” (electrophysical measurements) and “Elitron” with manual vibrators are used for electrospark hardening. However, using manual vibrators significantly increases the labour intensity and hardening time. Moreover, the surface quality after hardening with manual vibrators is often unsatisfactory. Various mechanized installations have been developed in order to reduce the labour intensity of electrospark hardening. Nevertheless, these installations are designed to harden specific parts and do not allow hardening tools of various designs, including woodcutting tools. The surface quality after hardening in mechanized installations does not always satisfy the customer. Further surface plastic deformation treatments, such as rolling and unrolling with rollers and balls, as well as diamond burnishing, are often used to improve the surface quality after electrospark hardening. The surface quality after additional processing by these methods boosts, although the labour intensity and cost of the hardening process increase. To increase the wear resistance of machine parts and tools, it is reasonable to reduce the height parameters of roughness, increase microhardness, and form the residual compressive stresses, which is ensured by the methods of surface plastic deformation. In this regard, it becomes necessary to use electrospark hardening simultaneously with surface plastic deformation. The work presents the design and features of using the device for hardening. The device was used to strengthen the thicknesser machine knives, which made it possible to almost double their durability. Applying this device, in comparison with using the electrospark hardening with a manual vibrator, reduces the roughness of the hardened surface and improves the surface quality of the processed workpieces. The modes of hardening have been installed, making it possible to effectively harden wood-cutting tools. For citation: Buglaev A.M. Device for Wood-Cutting Tool Hardening. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 5, pp. 134–141. DOI: 10.37482/0536-1036-2021-5-134-141

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