Селективный магнитный контроль толщины и степени упрочнения поверхностных слоев на стальных объектах

2021 ◽  
pp. 39-45
Author(s):  
А.В. Бызов ◽  
Д.Г. Ксенофонтов ◽  
В.Н. Костин ◽  
О.Н. Василенко
Keyword(s):  
Magnetic Flux ◽  
Internal Field ◽  
Hardened Layer ◽  
Strength Properties ◽  
Hardened Steel ◽  
Magnetic Characteristics ◽  
Surface Layers ◽  
Magnetic Parameters ◽  
Maximum Value ◽  
Tangential Field

The dependences of measured locally magnetic characteristics of surface-hardened steel objects on the thickness and physical properties of their surface layers are studied. It is shown theoretically and experimentally that a change in the thickness of the hardened layer on the surface of steel objects affects on the magnitude of the tangential field component on the surface of the object in the interpolar space significantly , as well as the change in the strength properties of the layer affects the magnitude of the magnetic flux in the "transducer-object" circuit. It is proposed to use this difference in magnetic parameters for selective testing of the surface hardening quality. It is shown that the coercive force measured locally by the internal field and the maximum value of the magnetic flux, which can be measured using a single transducer in single measuring cycle, can be used as diagnostic parameters.

Physical methods of research and monitoring

2019 ◽  
Vol 85 (1(I)) ◽  
pp. 35-44
Author(s):  
S. G. Sandomirski
Keyword(s):  
Heat Treatment ◽  
Coercive Force ◽  
Remanent Magnetization ◽  
Structural Changes ◽  
Mechanical Load ◽  
Magnetic Hysteresis ◽  
Steel Structures ◽  
Magnetic Characteristics ◽  
Magnetic Parameters ◽  
Saturation Intensity

The main magnetic parameters sensitive to the structure of steels are the parameters of their saturation loop of magnetic hysteresis: the coercive force Hcs and remanent magnetization Mrs. The saturation magnetization or saturation intensity Mr is most sensitive to the phase composition of steels. The variety of steel grades and modes of technological treatment (e.g., heat treatment, mechanical load) determined the use of magnetic structurescopy and magnetic characteristics — the coercive force Hc, remanent magnetization Mr , and specific hysteresis losses Wh on the subloops of the magnetic hysteresis of steels — as control parameters in diagnostics of the stressed and structural states of steel structures and pipelines. It has been shown that changes in Hc, Mr , and Wh are more sensitive to structural stresses and structures of steels than the parameters of the saturation hysteresis loop of magnetic hysteresis (Hcs, Mrs, and Mrs). The formulas for calculating Hc, Mr and Wh are presented to be used for estimation of changes in the parameters upon heat treatment of steels. Features of the structural sensitivity of the subloop characteristics and expediency of their use for magnetic structural and phase analyzes are determined. Thus, the range of changes in Ìr attributed to the structural changes in steels upon gradual Hm decrease is many times wider compared to the range of possible changes in Mrs under the same conditions. Conditions (relations between the magnetic parameters) and recommendations regarding the choice of the field strength Hm are given which provide the justified use of Hc, Mr and Wh parameters in magnetic structurescopy

Influence of surface layers on resistance spot joinability of partially hardened steel 22MnB5 with aluminum-silicon and zinc coatings

2020 ◽  
Vol 64 (5) ◽  
pp. 755-771
Author(s):  
Oleksii Sherepenko ◽  
Vincent Schreiber ◽  
Iwan Schischin ◽  
Maximilian Wohner ◽  
Philipp Wernlein ◽  
...  
Keyword(s):  
Hardened Steel ◽  
Surface Layers ◽  
Resistance Spot ◽  
Zinc Coatings ◽  
Aluminum Silicon

Research on Combined Processing Technology of Superficial Layers Hardened Steel

2016 ◽  
Vol 841 ◽  
pp. 21-28
Author(s):  
Petrică Corabieru ◽  
Stefan Velicu ◽  
Anişoara Corabieru ◽  
Dan Dragos Vasilescu ◽  
Ionel Păunescu
Keyword(s):  
Solid State ◽  
Liquid Phase ◽  
Cooling Rate ◽  
Hold Time ◽  
Hardened Steel ◽  
Operating Conditions ◽  
Technological Parameters ◽  
Surface Layers ◽  
Durability Analysis ◽  
Machined Parts

The novelty technology lies in the fact that the hardening of the surface layers is carried out both in liquid phase and in the solid state. Technology comprises three main stages with 12 technological phases.Experimentation highlights the viability of the technological procedure. The results of tests and verifications are the basis of the analysis of combined machined parts behavior in conditions similar to the operating conditions and of the analysis of the dependence between operation behavior and durability. Analysis of the results revealed the fact that failure to technological parameters: casting temperature; hold time at high temperatures; cooling rate after microalloying in liquid phase, gives rise to possible faults of the combined treated parts.

IMPROVING THE PERFORMANCE OF MINERAL CERAMIC BLADE CUTTING TOOLS

2021 ◽  
pp. 40-44
Author(s):  
Yu. M. Zubarev ◽  
M. A. Afanasenkov
Keyword(s):  
Chemical Elements ◽  
Cutting Tools ◽  
Vacuum Treatment ◽  
Hardened Layer ◽  
Configuration Model ◽  
Functional Surface ◽  
Surface Layers ◽  
Working Surface ◽  
Blade Cutting ◽  
Surface Hardened Layer

The article considers the possibility of improving the performance of mineral-ceramic cutting plates by removing most of the defects on their working surface due to the formation of functional surface layers by ion-vacuum treatment. A model of a surface-hardened layer for VOK-60 type ceramics is proposed. Based on the configuration model of the substance, chemical elements are selected for modifying the surface layer of ceramics. The results of laboratory and production tests that showed an increase in the performance of ceramic plates after implantation by at least two times are presented.

Modification of Strength Properties of Oxide Materials by Ion Irradiation

2018 ◽  
Vol 781 ◽  
pp. 70-75
Author(s):  
Sergei Ghyngazov ◽  
Valeria Kostenko ◽  
Sergey Shevelev ◽  
Anatoliy I. Kupchishin ◽  
Aleksey Kondratyuk
Keyword(s):  
Magnesium Oxide ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Strength Properties ◽  
Critical Stress Intensity Factor ◽  
Ceramic Technology ◽  
Surface Layers ◽  
Nanosecond Duration ◽  
Near Surface ◽  
Moderate Power

The effect of ion irradiation on the strength characteristics of magnesium oxide and ceramics based on zirconia is studied. The MgO samples were a single crystal grown in an artificial manner. Samples of zirconium ceramics were prepared by ceramic technology. Irradiation of MgO crystals was carried out by Si+ ions (E = 150 keV), Fe+ (E = 70 keV), C+ (E = 50 keV) at room temperature. The fluence varied within the range (1016–1017) сm–2. The modification of the investigated types of ceramics was carried out by ions Al+ (Е = 60 keV), Ar+ (Е= 60 keV), N+ (E = 50 keV). We used ion beams of microsecond duration and moderate power (the current density in the pulse was 3 10-3 A/cm2). Fluence was 1017 cm-2. The irradiation of the ceramics with an ion beam C+ (E = 50 keV) was also performed with nanosecond duration (τ = 50 ns). It is established that ionic irradiation of magnesium oxide leads to an increase in crack resistance and a critical stress intensity factor. Irradiation of ceramics leads to hardening of its near-surface layers.

scholarly journals Multiparameter method of surface hardening quality testing

2018 ◽  
Vol 224 ◽  
pp. 03016
Author(s):  
Vladimir Kostin ◽  
Olga Vasilenko ◽  
Alexander Byzov
Keyword(s):  
Coercive Force ◽  
Hysteresis Loop ◽  
Surface Hardening ◽  
Hardened Layer ◽  
Magnetic Characteristics ◽  
Software System ◽  
Residual Induction ◽  
Single Measurement ◽  
Measurement Results ◽  
Quality Testing

Measurements of the magnetic characteristics (coercive force, residual induction, induction of saturation) of objects that had different thicknesses of the hardened layer were made. The influence of an unstressed core on the measurement results, as well as the depth of the strengthened layer on the shape of the hysteresis loop, is investigated. The conclusion is made that it is possible to estimate the properties of a hardened layer by means of a single measurement with the help of the hardware-software system DIUS-1.15M

scholarly journals Gel Synthesis of Hexaferrites Pb1−xLaxFe12−xZnxO19 and Properties of Multiferroic Composite Ceramics PZT–Pb1−xLaxFe12−xZnxO19

Nanomaterials ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1630
Author(s):  
Inna V. Lisnevskaya ◽  
Inga A. Aleksandrova
Keyword(s):  
Coupling Coefficient ◽  
Lead Titanate ◽  
Electromechanical Coupling ◽  
Electromechanical Coupling Coefficient ◽  
Magnetic Characteristics ◽  
Composite Ceramics ◽  
Magnetic Parameters ◽  
Lead Titanate Zirconate ◽  
Multiferroic Composite ◽  
Tan Δ

We investigated the opportunities for obtaining hexaferrites Pb1−xLaxFe12−xZnxO19 (x = 0–1) from citrate–glycerin gel and showed that synthesis occurs via the formation of the Fe3O4 phase; products with a small amount of hematite impurity Fe2O3 can be obtained after firing at 800 to 900 °C with 0 ≤ x ≤ 0.5. If x > 0.5, perovskite-like LaFeO3 is formed in samples, so that if x = 0.9–1, the synthesis products virtually do not contain phases with hexaferrite structures and represent a mixture of LaFeO3, Fe2O3, and Fe3O4. Within the range of 0 ≤ x ≤ 0.5, the electrical and magnetic characteristics of hexaferrites Pb1−xLaxFe12−xZnxO19 are slightly dependent on x and have the following average values: A relative permittivity ε/ε0 ~ 45, a dielectric loss tangent tan δ ~ 0.6, an electrical resistivity R ~ 109 Ohm cm, coercivity Hc ~ 3 kOe, saturation magnetization Ms ~ 50 emu/g, and remanent magnetization Mr ~ 25 emu/g. The magnetoelectric (ME) ceramics 50 wt.% PZTNB-1 + 50 wt.% Pb1−xLaxFe12−xZnxO19 (PZTNB-1 is an industrial piezoelectric material based on lead titanate zirconate (PZT) do not contain impurity phases and have the following characteristics: Piezoelectric coefficients d33 = 10–60 and −d31 = 2–30 pC/N, piezoelectric voltage coefficients g33 = 2–13 and −g31 = 1–5 mV m/N, an electromechanical coupling coefficient Kp = 0.03–0.13, magnetic parameters Hc = 3–1 kOe, Ms = 50–30, and Mr = 25–12 emu/g. The maximum ME coupling coefficient ΔE/ΔH ~ 1.75 mV/(cm Oe) was achieved with x = 0.5.

scholarly journals Solar Surface Magnetoconvection

2003 ◽  
Vol 210 ◽  
pp. 169-180 ◽  
Author(s):  
Robert F. Stein ◽  
Åke Nordlund
Keyword(s):  
Magnetic Flux ◽  
Convection Zone ◽  
Solar Surface ◽  
Magnetic Energy ◽  
Mass Conservation ◽  
Small Scale ◽  
Surface Layers ◽  
Near Surface ◽  
Magnetic Structures ◽  
Deep Layers

Magnetoconvection simulations on meso-granule and granule scales near the solar surface are used to study small scale dynamo activity, the emergence and disappearance of magnetic flux tubes, and the formation and evolution of micropores.From weak seed fields, convective motions produce highly intermittent magnetic fields in the intergranular lanes which collect over the boundaries of the underlying meso-granular scale cells. Instances of both emerging magnetic flux loops and magnetic flux disappearing from the surface occur in the simulations. We show an example of a flux tube collapsing to kG field strength and discuss how the nature of flux disappearance can be investigated. Observed Stokes profiles of small magnetic structures are severely distorted by telescope diffraction and seeing.Because of the strong stratification, there is little recycling of plasma and field in the surface layers. Recycling instead occurs by exchange with the deep layers of the convection zone. Plasma and field from the surface descend through the convection zone and rise again toward the surface. Because only a tiny fraction of plasma rising up from deep in the convection zone reaches the surface due to mass conservation, little of the magnetic energy resides in the near surface layers. Thus the dynamo acting on weak incoherent fields is global, rather than a local surface dynamo.

Effects of Reactive Gas Compositions on the Magnetic Properties and Microstructures of FeTaNC Films

1996 ◽  
Vol 441 ◽  
Author(s):  
Tae-Hyuk Koh ◽  
Dong-Hoon Shin ◽  
Woon Choi ◽  
Dong-Hoon Ahn ◽  
Seoung-Eui Nam ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Flux ◽  
Magnetic Flux Density ◽  
Magnetic Characteristics ◽  
Soft Magnetic Properties ◽  
Soft Magnetic ◽  
Distinctive Difference ◽  
Co Addition ◽  
Soft Magnetism ◽  
Reactive Gas

AbstractSoft magnetic properties and microstructure evolutions of FeTaNC films were investigated, and compared with those of FeTaN and FeTaC films. Effects of substrate species (glass vs. CaTiO3) on the magnetic properties were also investigated. Co-addition of N and C enhances the grain refinements and soft magnetism compared with N or C only addition. Good soft magnetic characteristics of coercivity of 0.17 Oe, permeability of 4000 (5 MHz), and magnetic flux density of 17 kG can be obtained in the FeTaNC films with the relatively wide process ranges. While these values appear to be similar to those of FeTaN films on glass substrate, the most distinctive difference between FeTaNC and FeTaN (or C) films is the effects of substrate. Whereas FeTaNC films show good magnetic characteristics on both glass and CaTiO3 substrates, FeTaN (or C) films show substantial degradation on the CaTiO3 substrate.

Tribological characteristics of diamond-like films deposited with an are-discharge method

1990 ◽  
Vol 5 (11) ◽  
pp. 2524-2530 ◽  
Author(s):  
J-P. Hirvonen ◽  
R. Lappalainen ◽  
J. Koskinen ◽  
A. Anttila ◽  
T. R. Jervis ◽  
...  
Keyword(s):  
Sliding Wear ◽  
Wear Track ◽  
Carbon Film ◽  
Hardened Steel ◽  
Dry Sliding Wear ◽  
Transfer Layer ◽  
Maximum Value ◽  
Wear And Friction ◽  
Discharge Method

Using an are-discharge method, we deposited a diamond-like carbon film 600 nm thick on hardened steel. Characterization of the film was carried out with Raman spectroscopy. In dry sliding wear and friction tests, with a hardened steel pin as a counterpart, we obtained a friction coefficient between 10000 and 20000 cycles, with the maximum value of 0.18. The value decreased to 0.12 after about 100000 cycles. We obtained a wear coefficient of 7 × 10−17 m3/mN. A transfer layer formed on the pin during sliding and probably had the dominating effect on the tribological behavior. We observed in nanoindentation measurements that the film softened in a wear track during the first 20000 cycles. Although fracture pits on the wear track occurred, fracture is not the dominant failure mechanism of these films. Degradation of good tribological properties was caused mainly by partial wear-through of the film after 370000 cycles and by a subsequent redeposition of the transfer film on the wear track during prolonged sliding.

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