scholarly journals Flat surfaces machining by the magneto-abrasive method with permanent magnet end-type heads 1. The influence of the type of magneto-abrasive powder on the effectiveness of the magneto-abrasive machining

2020 ◽  
Vol 89 (2) ◽  
Author(s):  
Victor Maiboroda ◽  
Dmytro Dzhulii ◽  
Andrii Zelinko
Keyword(s):  
Permanent Magnet ◽  
Abrasive Machining ◽  
Flat Surfaces ◽  
Abrasive Powder

scholarly journals Flat surfaces machining by the magneto-abrasive method with permanent magnet end-type heads 3. The influence of the types of the working heads on the effectiveness of the magneto-abrasive machining

2021 ◽  
Vol 5 (1) ◽  
pp. 97-102
Author(s):  
Victor Maiboroda ◽  
Dmytro Dzhulii ◽  
Andrii Zelinko ◽  
Aleksey Burikov
Keyword(s):  
Permanent Magnet ◽  
Magnetic Induction ◽  
Feed Rate ◽  
Machining Process ◽  
Abrasive Machining ◽  
Technological Parameters ◽  
Supporting Surface ◽  
Flat Surfaces ◽  
Torus Type ◽  
Kinetics Of

Investigations of the magneto-abrasive machining (MAM) process of ferromagnetic flat surfaces by three types of end heads were carried out. The nature of the change in the magnitude of the magnetic induction in the working zones was determined. The influence of technological parameters of the machining process was investigated, such as the feed rate of the working heads, the frequency of their rotation about their axis, the size of the working gaps on the change in the parameters of the microroughness of the machined surfaces - Sa, Sp, Sv, the frequency distribution of heights microroughness and size of the supporting surface of the profile. It was shown that the level of roughness achieved after MAM is practically the same and does not exceed, under rational conditions of the MAM process, the values Sa = 0.05-0.07 μm, Sp = 0.2 μm and Sv = 0.39 μm with the only difference that the MAM process by the heads of the "brush-half of torus" type are being realized with increased productivity, especially in terms of reducing waviness and individual elements of the heredity of machining, determined by such factors as depth and feed rate during milling. The kinetics of the formation of a microprofile of surfaces is shown under various technological conditions of the MAM process.

scholarly journals Analysis of Magnetic Forces in the Working Clearance with Magnetic-Abrasive Treatment of Inductors on Standing Magnets

2022 ◽  
Author(s):  
A.M. Ikonnikov
Keyword(s):  
Magnetic Materials ◽  
Magnetic Induction ◽  
Software Package ◽  
Permanent Magnets ◽  
Abrasive Machining ◽  
Induction Method ◽  
Flat Surfaces ◽  
Abrasive Treatment ◽  
Magnetic Forces ◽  
Abrasive Powder

Abstract. The authors describe the method of calculating the magnetic forces in the working gap in the case of magnetically abrasive machining of flat surfaces of billets from magnetic materials by the periphery of a circular inductor on permanent magnets. The application of the software package ANSIS Maxwell for the calculation of the magnetic induction method in the working gap and the magnetic forces of the magnetically abrasive powder acting on the grain is shown. As a result of the work, the magnetic induction in the working gap was calculated for magnetically abrasive machining of flat surfaces of billets from magnetic materials by an inducer on permanent magnets. Also, calculations showed the distribution of the magnetic abrasive powder in the working gap, depending on the material of the workpiece being processed. In the case of magnetically abrasive machining of a magnetic workpiece, the powder in the working gap is concentrated in the zones with the greatest density of force lines - under the inductor poles. An analysis is made of the distribution of magnetic forces in the working gap during magnetic abrasive machining.

Application of Rare Earth Permanent Magnet on Magnetic Abrasive Machining

2007 ◽  
Vol 336-338 ◽  
pp. 712-714
Author(s):  
Y. Chen ◽  
Dong Ying Ju
Keyword(s):  
Magnetic Material ◽  
Heat Treatment ◽  
Rare Earth ◽  
Permanent Magnet ◽  
Magnetic Energy ◽  
Processing Technology ◽  
Raw Material ◽  
Treatment Technique ◽  
Abrasive Machining ◽  
Powder Sintering

Because of the raw material elements and its purity and so on, the Nd-Fe-B permanent magnet, the strongest magnetic material, which needs artificial synthesis, can hardly be used directly. The performance of the permanent magnet has not yet been greatly developed owing to the limitation of the artificial synthesizing technology, of the powder sintering technology and that of the application. In this paper, the magnetic abrasive machining method as a new application is put forward, and from this viewpoint, are discussed the performance and the processing technology of the permanent magnet and the magnetic abrasive machining method. A sintering route combining the direction heat treatment technique to increase the magnetic energy is suggested.

scholarly journals AISI 1045 Steel Flat Surfaces Machining Using the Magneto-Abrasive Method

2020 ◽  
Vol 7 (1) ◽  
pp. A1-A7
Author(s):  
V. S. Maiboroda ◽  
O. O. Belajev ◽  
D. Yu. Dzhulii ◽  
I. V. Slobodianiuk
Keyword(s):  
Permanent Magnets ◽  
Rotation Speed ◽  
Magnetic Field Gradient ◽  
Abrasive Tool ◽  
Abrasive Machining ◽  
Machined Surface ◽  
Flat Surfaces ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
1045 Steel

The results of the study of using the end-type heads based on permanent magnets for polishing flat surfaces of ferromagnetic parts on standard metal-working equipment are presented in the work. The possibility of a highly efficient achievement of the roughness of flat surfaces up to Ra < 0.05 μm with the initial Ra > 1–2 μm with removing of the heredity of the machining in the form of microwaves obtained in the face milling operation was shown. Based on the results of the analysis of the process of dispergation of the material was analyzed the influence of the magnetic field gradient the intensity of the magneto-abrasive machining of flat ferromagnetic surfaces by heads, which form a magneto-abrasive tool in the shape of a “brush” and “half of torus”. The influence of technological process parameters: the rotation speed of the working heads, the sizes of the working gap, the technological feed on the character of the change in the microgeometry of the machined surface were investigated. The machining conditions, under which occur the preferential machining of micro peaks or micro valleys on a rough surface, were identified. It was determined that the rational conditions of the magneto-abrasive machining of flat ferromagnetic surfaces are: the rotation speed of the working heads 900 rpm, the gap size between the machined surface and the working surface of the head 2.5–4.0 mm and the working feed 10–15 mm/min. Keywords: finishing, roughness, polishing, permanent magnet, magneto-abrasive tool.

scholarly journals Determining a rational scheme of machining of gas turbine engine essential parts in magnetorheological environments by the method of expert assessment

2019 ◽  
Vol 18 (3) ◽  
pp. 38-47
Author(s):  
A. G. Boytsov ◽  
S. V. Kurilovich ◽  
V. V. Kuritsyna ◽  
M. V. Siluyanova
Keyword(s):  
Permanent Magnet ◽  
Expert Assessment ◽  
Assessment Procedure ◽  
Abrasive Machining ◽  
Turbine Engine ◽  
Rational Scheme ◽  
Advantages And Disadvantages ◽  
Working Environments ◽  
Wide Range

The paper examines the basic schemes, features and advantages of magnetic abrasive machining. In this work we provide information on working environments for magnetic abrasive machining, compositions of ferro-abrasive powders and roughness of the surfaces achieved by their application; the process of forming the working layer is also analyzed. A classification of magnetic abrasive machining schemes according to the type of the magnetic inductor used, as well as their advantages and disadvantages are discussed. It is shown that the basic scheme of magnetic abrasive machining, the kind and dispersion of the abrasive medium, are assigned depending on the specific machining conditions and the requirements for the surface layer condition, whereas the choice of the type of the magnetic inductor is not so obvious, since each of the types has its advantages and disadvantages. An expert assessment procedure in choosing an acceptable magnetic-inductor scheme from a number of alternatives for use in magnetic abrasive machining is presented. The method of expert assessment was tested drawing on the example of the work of a group of experts formed by representatives of science and industry. It is shown that the direct-current electromagnetic inductor scheme is a rational scheme of magnetic abrasive machining according to the type of inductor used. This is due to the simplicity of process control and the expansion of technological capabilities, applicability for a wide range of problems solved by magnetic abrasive machining. Permanent-magnet magnetic abrasive schemes can be considered as an alternative to permanent-magnet ones.

Modeling of the Magnetic Abrasive Machining Process of Flat Surface Workpieces on Numerically Controlled Machine Tools

2015 ◽  
Vol 788 ◽  
pp. 69-74 ◽  
Author(s):  
Evgeniy Tatarkin ◽  
Aleksey Ikonnikov ◽  
Tatyana Schrayner ◽  
Roman Grebenkov
Keyword(s):  
Mathematical Model ◽  
Flat Surface ◽  
Cutting Parameters ◽  
Machining Process ◽  
Motion Trajectory ◽  
Abrasive Machining ◽  
Abrasive Powder ◽  
Finishing Process ◽  
The Mathematical Model ◽  
The Given

The article describes a mathematical model of the circular motion trajectory of a magnetic abrasive powder portion which participates in the magnetic abrasive machining process of flat surface workpieces. The motion trajectory of a magnetic abrasive powder portion is observed. The main formulas, assumptions and recommendations on the implementation of the mathematical model are introduced. Taking into account the feed rate of the machine table, rotational speed and the radius of the cylindrical magnetic inductor, the model allows determining an optimal amount of the magnetic abrasive powder portion which can provide the required efficiency of the finishing process. The magnetic abrasive machining process does not have any fixed standard cutting parameters, so they have to be readjusted every time. The given model can be used to predict the parameters of the finishing process of sophisticated flat surface workpieces.

HREM observation of dislocations near room temperature fractures in silicon

1988 ◽  
Vol 46 ◽  
pp. 892-893
Author(s):  
M. H. Rhee ◽  
W. A. Coghlan
Keyword(s):  
Cross Section ◽  
Room Temperature ◽  
Single Crystal Silicon ◽  
Dislocation Nucleation ◽  
Back Side ◽  
Ion Milling ◽  
Crystal Silicon ◽  
Flat Surfaces ◽  
Induced Fractures ◽  
Vicker’S Microhardness

Silicon is believed to be an almost perfectly brittle material with cleavage occurring on {111} planes. In such a material at room temperature cleavage is expected to occur prior to any dislocation nucleation. This behavior suggests that cleavage fracture may be used to produce usable flat surfaces. Attempts to show this have failed. Such fractures produced in semiconductor silicon tend to occur on planes of variable orientation resulting in surfaces with a poor surface finish. In order to learn more about the mechanisms involved in fracture of silicon we began a HREM study of hardness indent induced fractures in thin samples of oxidized silicon.Samples of single crystal silicon were oxidized in air for 100 hours at 1000°C. Two pieces of this material were glued together and 500 μm thick cross-section samples were cut from the combined piece. The cross-section samples were indented using a Vicker's microhardness tester to produce cracks. The cracks in the samples were preserved by thinning from the back side using a combination of mechanical grinding and ion milling.

A TEM study of electron tunneling in biological macromolecules

1987 ◽  
Vol 45 ◽  
pp. 140-141
Author(s):  
J. A. Panitz
Keyword(s):  
Stark Effect ◽  
Electron Tunneling ◽  
Imaging Modality ◽  
Tunneling Current ◽  
Biological Species ◽  
Scanning Tunneling ◽  
Biological Macromolecules ◽  
Flat Surfaces ◽  
Virus Particles ◽  
Stm Images

Tunneling is a ubiquitous phenomenon. Alpha particle disintegration, the Stark effect, superconductivity in thin films, field-emission, and field-ionization are examples of electron tunneling phenomena. In the scanning tunneling microscope (STM) electron tunneling is used as an imaging modality. STM images of flat surfaces show structure at the atomic level. However, STM images of large biological species deposited onto flat surfaces are disappointing. For example, unstained virus particles imaged in the STM do not resemble their TEM counterparts.It is not clear how an STM image of a biological species is formed. Most biological species are large compared to the nominal electrode separation of ∼ 1nm that is required for electron tunneling. To form an image of a biological species, the tunneling electrodes must be separated by a distance that would normally be too large for a tunneling current to be observed.

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