scholarly journals The Effect of Vibro-Finishing Treatment on The Porosity of the Surface Layer of Powder Metallurgy Products

2019 ◽  
Vol 297 ◽  
pp. 04006
Author(s):  
Yuriy Ankudimov ◽  
Irina Sadovaya ◽  
Dieudonne Essola ◽  
Tatyana Bagdasaryan
Keyword(s):  
Surface Layer ◽  
Powder Metallurgy ◽  
Powder Material ◽  
Functional Dependence ◽  
Particle Interaction ◽  
Experimental Studies ◽  
Surface Plastic Deformation ◽  
Powder Materials ◽  
Surface Plastic ◽  
Porosity Reduction

The article is devoted to the methods of surface plastic deformation treatment to change the porosity of parts obtained from powder materials. Functional dependences between the concentration of the solid part of the system and the size of the plastic print on the example of vibro-finishing and hardening treatment (VF and HT) are established. The reduction in porosity upon hardening of the surface material is experimentally confirmed. The results can be used to predict the surface porosity of powder metallurgy products that have undergone additional processing of SPD, as well as for further studies of the field of application of (VF and HT). Based on the particle interaction in the working medium with the part surface made from powder material, we obtained functional dependence of the density coefficient of the surface layer of the powder material after (VF and HT). Experimental studies were carried out on samples of powdered iron PK6. The porosity of the samples was determined by stereoscopic metallography, microhardness of the surface layer - on hardness tester. Everything was performed by standard methods. The results were presented in a series of porosity charts. Maximum hardening is 30% of almost twofold porosity reduction. The experts in the field of powder metallurgy may be interested in the obtained results.

Study of Surface Layer Hardening after Treatment Complex Tool

2020 ◽  
Vol 303 ◽  
pp. 89-96
Author(s):  
K.S. Mitrofanova
Keyword(s):  
Plastic Deformation ◽  
Surface Layer ◽  
Strain State ◽  
Experimental Studies ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Technological Inheritance ◽  
Multiple Loading ◽  
Surface Layer Hardening ◽  
Solidified Body

The results of experimental studies of the thin surface layer of samples made of steel 45 after treatment with surface plastic deformation (SPD) multiradius roller (MR-roller) are presented. On the basis of the apparatus of the mechanics of technological inheritance, taking into account the effect of the solidified body, a model of the process according to the scheme of multiple loading-unloading of metal, taking into account the phenomenology of the SPD process and the properties of the material, is created. Distributions of parameters of the stress-strain state in the deformation centre are obtained, the parameters of roughness and microhardness of the surface layer are investigated.

scholarly journals The Study of Multiradius Roller Running Process

2019 ◽  
Vol 297 ◽  
pp. 05003
Author(s):  
Andrey Krechetov ◽  
Kristina Mitrofanova
Keyword(s):  
Plastic Deformation ◽  
Surface Layer ◽  
Hydrostatic Pressure ◽  
Experimental Studies ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Engineering Technology ◽  
Processed Material ◽  
Sample Structure ◽  
Single Radius

The results of theoretical and experimental studies of the surface of the sample of steel 45 after surface plastic deformation (SPD) with multi-radius roller (MR-roller) is shown. The goal of this study is to expand the technological capabilities of the method of SPD through the use of a new design of the deforming tool developed at the Department of Engineering Technology of KuzSTU. The advantage of the MR-roller (Patent RU № 2557377) over the traditional tool for SPD (single-radius roller) is the possibility of creating a large hydrostatic pressure in the deformation zone, without destroying the surface layer of the processed material. The research technique included finite element modeling (FEM), microhardness measurement, metallographic studies of the sample structure. As a result of the study, some regularities of the process of hardening by a multi-radius tool with high hydrostatic pressure and a large number of quasi-monotonic deformation sites were revealed. The results indicate a significant hardening without metal destruction and the formation of nanoscale grains, which allows to improve the properties of rolled products in the application of high operating loads.

scholarly journals Application of roller burnishing technologies to improve the wear resistance of submerged pump parts made of powder alloys

2018 ◽  
Vol 19 (7) ◽  
pp. 705 ◽  
Author(s):  
Elena Kropotkina ◽  
Marina Zykova ◽  
Alexander Shein ◽  
Natalya Kapustina
Keyword(s):  
Surface Layer ◽  
Experimental Studies ◽  
Surface Plastic Deformation ◽  
Wear Intensity ◽  
Surface Plastic ◽  
Submersible Pump ◽  
Roller Burnishing ◽  
Powder Alloys ◽  
Iron Copper ◽  
Layer Resistance

This paper presents experimental studies of the influence of surface plastic deformation (SPD) (roller burnishing) on the properties of the surface layer of a part “guide apparatus” of the centrifugal submersible pump for oil production. The parts made of composite powder alloys based on the iron-copper system were taken as an object of researches. The microstructure of the surface layer of the samples, surface roughness, microhardness, and hardness were studied. Testing of the samples for the surface layer resistance to abrasive wear according to the Calotest method showed a decrease in the wear intensity by 1.5–1.6 times in comparison to samples without SPD.

scholarly journals INCREASING THE EFFICIENCY OF SURFACE STRENGTHENING OF METAL PRODUCTS BY COMBINED THERMODEFORMATION PROCESSING

2020 ◽  
pp. 103-110
Author(s):  
Oleksandr Danyleiko ◽  
Vitaliy Dzhemelinskyi ◽  
Dmytro Lesyk ◽  
Artemii Bernatskyi
Keyword(s):  
Surface Layer ◽  
Laser Beam ◽  
Surface Hardening ◽  
Thermal Deformation ◽  
Experimental Studies ◽  
Numerical Control ◽  
Surface Plastic ◽  
Beam Diameter ◽  
Metal Products ◽  
Deformation Surface

The article discusses the prospects of using combined thermal deformation surface processing to improve the performance properties of metal products. There is a new method of thermal deformation surface hardening (shot peening (SP) followed by laser heat treatment (LHT)) for tools and crown housings operating under difficult conditions proposed. For carrying out experimental studies, flat samples of 30KhGSA steel and steel 45 were selected. Preliminary hardening and finishing with static or dynamic methods of surface plastic deformation were carried out on a modernized installation based on a DYNAMITE 2800 numerical control machine, and SP was implemented on industrial equipment. Laser surface hardening of the samples was carried out in single passes with a sample moving speed of 300...500 mm/min with a laser beam diameter of 7.3 mm and a laser power of 1 kW using the ROFIN-SINAR DY 044 technological unit. The optimal regimes of surface hardening are determined under the deformation action of a gas-dynamic flow with solid particles and thermal action by a laser beam to obtain maximum values ​​of hardening depth and hardness. In particular, with SP, the gas-feed stream feed pressure is 0.5 MPa, the processing time is 1 min, regardless of the type of material. The optimal laser beam power is 1 kW at a sample travel speed of 300 mm/min. There are the results of experimental studies of the change in the hardening depth as a function of time and pressure after SP, the speed of movement of the treated sample from carbon steel 45 and medium alloyed steel 30KhGSA after LHT and combined SP+LHT, and also the distribution of microhardness over the depth of the hardened layer presented. It is revealed that the combined SP+LHT of 30 KhGSA steel at optimal modes forms 1.5 times (1.3 mm) greater depth of the strengthened surface layer in comparison with LHT, while providing the surface layer hardness of ~5400 MPa.

Acoustic and Emission Control of the Hereditable Stress and Strain State of the Metal Surface Layer during Cutting and Surface Plastic Deformation

2015 ◽  
Vol 788 ◽  
pp. 3-10
Author(s):  
Valeriy Yu. Blumenstein ◽  
Fyodor I. Panteleenko ◽  
Igor V. Miroshin ◽  
Oleg A. Ostanin
Keyword(s):  
Plastic Deformation ◽  
Acoustic Emission ◽  
Surface Layer ◽  
Shear Deformation ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Deformation Degree ◽  
Emission Signal ◽  
Experimental Findings ◽  
Surface Layer Quality

Methods and experimental findings shown describe how mechanical parameters of the surface layer behavior and acoustic emission signals are interconnected.Experimental study was carried out under conditions of simple single-and dual stage compression. Graphic and analytic dependencies between the counting rate of the acoustic emission Ṅ and the shear deformation degree Λ were revealed. The findings describing dual compression show that the acoustic emission method is sensitive to the material stressing history.The dependency of the acoustic emission signal energy on the pre-stressing program was found, which helped establish that, with values of the plasticity reserve depletion being equal for all experimental specimens, the accumulated shear deformation degree Λ was different.The findings describing the hereditable physical state of the strengthened surface layer of parts during cutting and surface plastic deformation are presented in the paper. The study was carried out using the methods of property accumulation control in deformation sites depending on treatment modes with real-time monitoring of acoustic emission signals. A peculiar feature of these methods is the use of visual recording of the metal plastic flow to be further used in calculating the hereditable parameters of the surface layer quality.

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.

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