The structure of Ti-Ta welded joint and microhardness distribution over the cross section

2018 ◽  
Author(s):  
Aleksandr A. Fomin ◽  
Vladimir Koshuro ◽  
Ivan Egorov ◽  
Andrey Shelkunov ◽  
Andrey Zakharevich ◽  
...  
Keyword(s):  
Cross Section ◽  
Welded Joint ◽  
Microhardness Distribution ◽  
The Cross

CHANGES IN THE MICROSTRUCTURE AND MICROHARDNESS OF 65G STEEL AFTER THERMAL HARDENING AND SURFACING WITH A LOW-CARBON ELECTRODE

2021 ◽  
Vol 1 (142) ◽  
pp. 107-114
Author(s):  
Aleksandr Mikhal’chenkov ◽  
◽  
Sergey Fes’kov ◽  
Irina Kozarez ◽  
Elena Slezko
Keyword(s):  
Wear Resistance ◽  
Fusion Zone ◽  
Cross Section ◽  
Surface Friction ◽  
Research Purpose ◽  
Low Carbon ◽  
Thermal Hardening ◽  
Microhardness Distribution ◽  
The Cross ◽  
Shock Zone

When reinforcing the surfaces of the working bodies of tillage tools, they are surfaced with electrodes with a low-carbon rod. The surface in contact with the soil is not subjected to heat treatment. Recently, thermal hardening of local parts has been used. (Research purpose) The research purpose is in studying the transformation of the microstructure of 65G heat-strengthened steel deposited by an electrode with a low-carbon rod, as well as the specifics of the microhardness distribution in this section. (Materials and methods) Investigated in the cross-section of the structure of the deposited area by the standard method, consisting in the preparation of microsections, etching and directly microanalysis. (Results and discussion) The transformation of the microstructure of heat-strengthened steel 65G deposited by an electrode with a low-carbon rod is complex due to the specificity and versatility of the phase transformations that occur during its formation. The microhardness distribution plot in the cross-section of the surfacing area has a complex configuration, determined by the variety of structural components, the presence of deformation processes during crystallization and solidification, and the presence of preliminary thermal hardening of the base metal. (Conclusions) Increased values of the hardness of individual areas contribute to an increase in the abrasive wear resistance of the part. The presence of the fusion zone ensures the resistance of the deposited area to cracking. The zone of thermal influence has four clearly distinguishable areas: the drop in microhardness; the stable values according to the Vickers method; the near-shock zone; the fusion zone. The microhardness of the weld surface of the cushion is 410 Vickers or 42 Rockwell, which creates conditions for increasing the wear resistance of the surface friction. The use of electrodes with a low-carbon rod is advisable when conducting surfacing reinforcement of heat-strengthened steels.

scholarly journals A Connection Method between Ultrahard PtW8 Wire and a Au Thick Film Based on Parallel-Gap Resistance Microwelding

Materials ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 2911
Author(s):  
Mingqiang Pan ◽  
Minghui Tu ◽  
Jizhu Liu
Keyword(s):  
Thick Film ◽  
Gas Sensor ◽  
Cross Section ◽  
Joint Strength ◽  
Welded Joint ◽  
Experimental System ◽  
Tungsten Alloy ◽  
Welding Line ◽  
The Cross ◽  
Application Requirements

To meet the application requirements of a thermal gas sensor, it is necessary to realize a bond connection between PtW8 wire with a Au thick film. However, the physical properties, such as the melting point and hardness, of the two materials differ greatly. In this study, the parallel-gap resistance microwelding was introduced into the bonding connection between PtW8 wire and a Au thick film in the thermal gas sensor. The feasibility of the method was analyzed theoretically and the experimental system was established and studied. A scanning electron microscope (SEM) was used to analyze the morphology of the cross-section of the welded joint. The results showed that there was no obvious transition layer at the interface region but there were relatively dense welds. At the same time, it was found that the melted Au wetted and climbed on the surface of the platinum-tungsten alloy, which may have been the key to forming the joint. Elements were observed to have a spatial distribution gradient within the cross-section of the welding line, revealing that mutual diffusion occurred in the parallel-gap resistance microwelding, where this diffusion behavior may be the basic condition for forming the joint. Finally, the influence of the welding voltage, time, and force on the joint strength was also studied, where the joint strength could be up to 5 cN.

scholarly journals Effect of Tool Rotational Speed on the Microstructure and Mechanical Properties of Bobbin Tool Friction Stir Welded 6082-T6 Aluminum Alloy

Metals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 894 ◽  
Author(s):  
Yupeng Li ◽  
Daqian Sun ◽  
Wenbiao Gong
Keyword(s):  
Aluminum Alloy ◽  
Cross Section ◽  
Heat Affected Zone ◽  
Rotational Speed ◽  
Maximum Temperature ◽  
Friction Stir ◽  
Fracture Location ◽  
Microhardness Distribution ◽  
Average Grain Size ◽  
The Cross

Samples of 6082-T6 aluminum alloy were welded by bobbin tool friction stir welding at different rotational speeds. The thermal cycles, microstructure, microhardness, and tensile properties of the specimens were investigated. The results show that the maximum temperature at the joint increases first and then decreases with increasing rotational speed, and the maximum temperature is 509 °C at 1000 r/min. The macromorphology of the cross-section of the joint is rectangular, and an ‘’S” line and gray-white texture can be observed. The stirred zone had much smaller equiaxed recrystallized grains. With increasing welding speed, the average grain size in the stirred zone region decreases. The microhardness distribution of the cross-section of all joints is W-shaped. When the rotational speed increases, the hardness of the heat-affected zone decreases gradually, and the hardness of the stirred zone increases. At 600 r/min, the strength is the lowest. The fracture location is between the stirred zone and the thermomechanically affected zone. When the rotational speed is increased, the fracture location is entirely located in the heat affected zone, and the fracture surface is dimple-like; the strength significantly increases and reaches a maximum at 800 r/min.

CHANGES IN THE MICROSTRUCTURE AND MICROHARDNESS OF 65G STEEL AFTER THERMAL HARDENING AND SURFACING WITH A LOW-CARBON ELECTRODE

2021 ◽  
Vol 1 (142) ◽  
pp. 107-114
Author(s):  
Aleksandr M. Mikhal’chenkov ◽  
◽  
Sergey A. Fes’kov ◽  
Irina V. Kozarez ◽  
Elena I. Slezko
Keyword(s):  
Wear Resistance ◽  
Fusion Zone ◽  
Cross Section ◽  
Surface Friction ◽  
Research Purpose ◽  
Low Carbon ◽  
Thermal Hardening ◽  
Microhardness Distribution ◽  
The Cross ◽  
Shock Zone

When reinforcing the surfaces of the working bodies of tillage tools, they are surfaced with electrodes with a low-carbon rod. The surface in contact with the soil is not subjected to heat treatment. Recently, thermal hardening of local parts has been used. (Research purpose) The research purpose is in studying the transformation of the microstructure of 65G heat-strengthened steel deposited by an electrode with a low-carbon rod, as well as the specifics of the microhardness distribution in this section. (Materials and methods) Investigated in the cross- section of the structure of the deposited area by the standard method, consisting in the preparation of microsections, etching and directly microanalysis. (Results and discussion) The transformation of the microstructure of heat-strengthened steel 65G deposited by an electrode with a low-carbon rod is complex due to the specificity and versatility of the phase transformations that occur during its formation. The microhardness distribution plot in the cross-section of the surfacing area has a complex configuration, determined by the variety of structural components, the presence of deformation processes during crystallization and solidification, and the presence of preliminary thermal hardening of the base metal. (Conclusions) Increased values of the hardness of individual areas contribute to an increase in the abrasive wear resistance of the part. The presence of the fusion zone ensures the resistance of the deposited area to cracking. The zone of thermal influence has four clearly distinguishable areas: the drop in microhardness; the stable values according to the Vickers method; the near-shock zone; the fusion zone. The microhardness of the weld surface of the cushion is 410 Vickers or 42 Rockwell, which creates conditions for increasing the wear resistance of the surface friction. The use of electrodes with a low-carbon rod is advisable when conducting surfacing reinforcement of heat-strengthened steels.

scholarly journals Application of analytical methods for determination of hardness distribution in welded joint made of S1100QL steel

2018 ◽  
Vol 157 ◽  
pp. 02041 ◽  
Author(s):  
Wiesława Piekarska ◽  
Milan Sága ◽  
Dorota Goszczyńska-Króliszewska ◽  
Tomasz Domański ◽  
Peter Kopas
Keyword(s):  
Numerical Simulation ◽  
Cross Section ◽  
Analytical Methods ◽  
Welded Joint ◽  
Volume Fraction ◽  
Welding Process ◽  
Hardness Distribution ◽  
The Cross ◽  
Methods Analytical

The prediction of hardness distribution in the cross section of welded join made of S1100QL steel is performed in this study on the basis of analytical methods. Analytical CCT diagram and volume fraction of each phases of S1100QL steel as a function of cooling time t8/5 are determined. A numerical simulation of welding process is performed in ABAQUS. Thermal cycles and temperature field in welded joints are determined. Prediction of hardness distribution in the cross section of the joint is performed on the basis of obtained cooling times t8/5. Results of numerical simulations are compared with experimentally obtained results.

CONTROLLED FORMATION OF THE DESIGNED MECHANICAL PROPERTIES OF MACHINE PARTS BY DEFORMATION HARDENING IN THE CONDITIONS OF COMPLEX LOCAL LOADING OF THE DEFORMATION ZONE

2020 ◽  
Vol 2 ◽  
pp. 34-42
Author(s):  
S.Yu. RADCHENKO ◽  
V.A. GOLENKOV ◽  
D.O. DOROKHOV
Keyword(s):  
Mechanical Properties ◽  
Cross Section ◽  
Deformation Zone ◽  
Cast Alloy ◽  
Processing Parameters ◽  
Local Loading ◽  
Technological Parameters ◽  
Microhardness Distribution ◽  
Deformation Hardening ◽  
The Cross

The process of complex local loading of the deformation zone is considered using the example of processing a sleeve made of a bronze alloy, the mechanical properties of the cast alloy under study were determined, and the parameters of the microhardness distribution over the cross section of the processed workpiece were investigated. Plots of the distribution of various microhardness parameters over the cross section are plotted depending on the number of processing cycles. A mathematical model of the process under consideration and its comparison with experimental data is shown. The description of the technique in the form of an algorithm of actions for the appointment of technological parameters. An example is presented in the form of a finished nomogram for the assignment of specific processing parameters to obtain a given hardening depth and value.

A New Approach to the Demonstration of Oxidase-Localization Using Tannic Acid Or Catechin

1973 ◽  
Vol 31 ◽  
pp. 698-699
Author(s):  
V. Mizuhira ◽  
Y. Futaesaku
Keyword(s):  
Cross Section ◽  
Tannic Acid ◽  
Elastic Fiber ◽  
The Other ◽  
New Approach ◽  
Tissue Block ◽  
Active Reaction ◽  
The Cross

Previously we reported that tannic acid is a very effective fixative for proteins including polypeptides. Especially, in the cross section of microtubules, thirteen submits in A-tubule and eleven in B-tubule could be observed very clearly. An elastic fiber could be demonstrated very clearly, as an electron opaque, homogeneous fiber. However, tannic acid did not penetrate into the deep portion of the tissue-block. So we tried Catechin. This shows almost the same chemical natures as that of proteins, as tannic acid. Moreover, we thought that catechin should have two active-reaction sites, one is phenol,and the other is catechole. Catechole site should react with osmium, to make Os- black. Phenol-site should react with peroxidase existing perhydroxide.

Energy Distribution in Electron Beams

1972 ◽  
Vol 30 ◽  
pp. 568-569
Author(s):  
Tamotsu Ohno
Keyword(s):  
Electron Beam ◽  
Energy Distribution ◽  
Cross Section ◽  
Integral Curve ◽  
Electron Beams ◽  
Electron Gun ◽  
Angular Divergence ◽  
Apparent Increase ◽  
Integral Width ◽  
The Cross

The energy distribution in an electron; beam from an electron gun provided with a biased Wehnelt cylinder was measured by a retarding potential analyser. All the measurements were carried out with a beam of small angular divergence (<3xl0-4 rad) to eliminate the apparent increase of energy width as pointed out by Ichinokawa.The cross section of the beam from a gun with a tungsten hairpin cathode varies as shown in Fig.1a with the bias voltage Vg. The central part of the beam was analysed. An example of the integral curve as well as the energy spectrum is shown in Fig.2. The integral width of the spectrum ΔEi varies with Vg as shown in Fig.1b The width ΔEi is smaller than the Maxwellian width near the cut-off. As |Vg| is decreased, ΔEi increases beyond the Maxwellian width, reaches a maximum and then decreases. Note that the cross section of the beam enlarges with decreasing |Vg|.

Research in the cross-section of community psychology and global climate change: A call for action

2009 ◽  
Author(s):  
Marci Culley ◽  
Holly Angelique ◽  
Courte Voorhees ◽  
Brian John Bishop ◽  
Peta Louise Dzidic ◽  
...  
Keyword(s):  
Climate Change ◽  
Cross Section ◽  
Global Climate Change ◽  
Community Psychology ◽  
Global Climate ◽  
The Cross

Experimental Studies Of Multilayer Glass Structures On Compression, Compression With Bending And Simple Bending

2019 ◽  
pp. 22-30
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Applied Load ◽  
Experimental Studies ◽  
Strength Properties ◽  
Research Topic ◽  
Normative Values ◽  
Laminated Glass ◽  
The Cross ◽  
Experimental Values

The work of multilayer glass structures for central and eccentric compression and bending are considered. The substantiation of the chosen research topic is made. The description and features of laminated glass for the structures investigated, their characteristics are presented. The analysis of the results obtained when testing for compression, compression with bending, simple bending of models of columns, beams, samples of laminated glass was made. Overview of the types and nature of destruction of the models are presented, diagrams of material operation are constructed, average values of the resistance of the cross-sections of samples are obtained, the table of destructive loads is generated. The need for development of a set of rules and guidelines for the design of glass structures, including laminated glass, for bearing elements, as well as standards for testing, rules for assessing the strength, stiffness, crack resistance and methods for determining the strength of control samples is emphasized. It is established that the strength properties of glass depend on the type of applied load and vary widely, and significantly lower than the corresponding normative values of the strength of heat-strengthened glass. The effect of the connecting polymeric material and manufacturing technology of laminated glass on the strength of the structure is also shown. The experimental values of the elastic modulus are different in different directions of the cross section and in the direction perpendicular to the glass layers are two times less than along the glass layers.

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