Effects of Contact Modes on Wear of Railroad

2005 ◽  
Author(s):  
Pranay Asthana ◽  
Hong Liang
Keyword(s):  
Electron Microscope ◽  
Surface Characterization ◽  
Friction And Wear ◽  
Wear Behavior ◽  
Sodium Borate ◽  
Wear Volume ◽  
Contact Conditions ◽  
X Ray ◽  
Friction And Wear Mechanisms ◽  
Scanning Electron

In this study the wear behavior of rail road steel under rolling with sliding and pure sliding conditions was investigated. Experiments were conducted using a modified linear reciprocating tribometer. Friction and wear were estimated against different conditions. Surface characterization techniques include a scanning electron microscope (SEM) with attached energy dispersive X-ray (EDX) for wear and tribochemical wear studies. It was found that rolling with sliding provided higher friction and wear than pure sliding. The addition of crystalline hydrated sodium borate (Na2B4O7-10H2O) increased friction in both contact conditions, while there was a significant decrease in the wear volume. This research proposes new friction and wear mechanisms.

Effect of Sliding Speed on Wear Property of MoSi2 at High Temperature

2011 ◽  
Vol 66-68 ◽  
pp. 150-154
Author(s):  
Hou An Zhang ◽  
Si Yong Gu
Keyword(s):  
Electron Microscope ◽  
High Temperature ◽  
Friction Coefficient ◽  
Wear Rate ◽  
Friction And Wear ◽  
Wear Property ◽  
Sliding Speed ◽  
X Ray ◽  
Very High ◽  
Scanning Electron

Wear behaviors of MoSi2against Al2O3or SiC under 30N at 1000°C in air have been investigated by using an XP-5 type High Temperature Friction and Wear Tester. The worn surfaces and phases of samples were characterized by scanning electron microscope (SEM) and X-ray diffractometer, respectively. Result shows the wear rate and friction coefficient of MoSi2decreases with the increase of sliding speed. SiC is superior to Al2O3as the counter-face materials of MoSi2. Serious adhesion leads to very high wear rate of Al2O3in this experiment. SiC shows a surprising mass weighing phenomenon, which is caused by oxidation. The main wear mechanism of MoSi2against Al2O3is oxidation and adhesion. However when against SiC, it is chiefly controlled by grinding.

EFFECT OF La2O3 ADDITION ON MICROSTRUCTURE AND WEAR BEHAVIOR OF ELECTROSPARK DEPOSITED Ni-BASED COATINGS

2013 ◽  
Vol 20 (06) ◽  
pp. 1350060 ◽  
Author(s):  
GAO YUXIN ◽  
YI JIAN
Keyword(s):  
Wear Resistance ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Wear Behavior ◽  
Deposition Technique ◽  
Electrospark Deposition ◽  
X Ray ◽  
Wear Process ◽  
Hardness Tester ◽  
Scanning Electron

La 2 O 3 doped Ni -based coatings have been prepared by electrospark deposition technique. The effect of La 2 O 3 on the microstructure, hardness and wear behavior of the as-prepared Ni -based coatings is investigated by using X-ray diffractometer, scanning electron microscope, wear tribometer and Vickers hardness tester. Results indicates that the microstructure, hardness and wear resistance of La 2 O 3 doped Ni -based coatings are effectively improved as compared to the undoped one, and the coating with the addition of 2.5 wt.% La 2 O 3 shows the optimal improvement effects. The addition of La 2 O 3 can reduce the defects, refine grains and increase hardness of the coating, which can inhibit the nucleation and propagation of cracking, consequently resist cutting and fracture during the wear process. Moreover, the addition of La 2 O 3 leads to changes in abrasion mechanism of the coatings, and the reasons resulting in different abrasion mechanisms are discussed.

On the Tribological Properties of RGO-MoS2 Composites Surface Modified by Oleic Acid

2021 ◽  
Author(s):  
TianXia LIU ◽  
jian Qin ◽  
Jian Wang ◽  
jing Li
Keyword(s):  
Graphene Oxide ◽  
Oleic Acid ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Molybdenum Disulfide ◽  
Photoelectron Spectroscopy ◽  
Friction And Wear ◽  
X Ray ◽  
Surface Modified ◽  
Scanning Electron

Abstract Purpose To study the effect of oleic acid surface modified RGO/MoS2 composite lubricating additives on the friction and wear properties of 10# White Oil (10# WO). Method The influence of different concentrations of reduction graphene oxide/molybdenum disulfide (RGO-MoS2) and oleic acid surface modified reduction graphene oxide/molybdenum disulfide (OA-RGO-MoS2) on the lubricating properties in 10# WO was investigated by using a four-ball long-term friction and wear tester. The microscopic morphology, lattice structure, composition and element valence of the prepared material were characterized by scanning electron microscope, Raman spectroscopy, X-ray diffractometer, X-ray photoelectron spectroscopy, element analyzer and other instruments. The diameter, structure, morphology, composition and element valence state of the wear scar were obtained by multifunctional universal tool microscope, scanning electron microscope and X-ray photoelectron spectroscopy. Result In the RGO-MoS2 white oil system, when 0.4 wt% RGO-MoS2 was added, the anti-friction effect was the best, and the average friction coefficient (AFC) reduced by 21.8%. When 0.2 wt% RGO-MoS2 was added, the anti-wear effect was the optimal, and the average wear scar diameter (AWSD) decreased by 12.4%. In the OA-RGO-MoS2 white oil system, when 0.2 wt% OA-RGO-MoS2 was added, the anti-friction and anti-wear effects were the best, and the AFC reduced by 33.3%, and AWSD reduced by 14.1%. Conclusion Compared with RGO-MoS2, OA-RGO-MoS2 has a higher degree of graphitization, larger interlayer spacing, lower degree of layered accumulation, higher MoS2 load, and weaker thermal stability. Both lubricating additives have good anti-friction and anti-wear effects at low concentrations, and the anti-friction and anti-wear effects are more prominent after being modified by oleic acid. Analysis of friction mechanism shows that a lubricating protective film containing iron, oxygen, molybdenum, carbon, and sulfur is formed through adsorption or tribochemical reaction during the friction process, which improves the lubrication state and plays a role in reducing friction and anti-wear.

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

1973 ◽  
Vol 31 ◽  
pp. 132-133 ◽  
Author(s):  
R. E. Herfert
Keyword(s):  
Surface Characterization ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Depth Of Penetration ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

X-ray micro tomography in the scanning electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 106-107 ◽  
Author(s):  
W. Brünger
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Target Surface ◽  
The Body ◽  
X Rays ◽  
Cross Sectional ◽  
X Ray ◽  
Micro Tomography ◽  
Scanning Electron

Reconstructive tomography is a new technique in diagnostic radiology for imaging cross-sectional planes of the human body /1/. A collimated beam of X-rays is scanned through a thin slice of the body and the transmitted intensity is recorded by a detector giving a linear shadow graph or projection (see fig. 1). Many of these projections at different angles are used to reconstruct the body-layer, usually with the aid of a computer. The picture element size of present tomographic scanners is approximately 1.1 mm2.Micro tomography can be realized using the very fine X-ray source generated by the focused electron beam of a scanning electron microscope (see fig. 2). The translation of the X-ray source is done by a line scan of the electron beam on a polished target surface /2/. Projections at different angles are produced by rotating the object.During the registration of a single scan the electron beam is deflected in one direction only, while both deflections are operating in the display tube.

PHAX-SCAN: Functional integration of a Scanning Electron Microscope and an energy-dispersive x-ray analyser

1989 ◽  
Vol 47 ◽  
pp. 56-57
Author(s):  
Marc H. Peeters ◽  
Max T. Otten
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
High Speed ◽  
High Performance ◽  
Functional Integration ◽  
Energy Dispersive ◽  
X Rays ◽  
X Ray ◽  
High Speed Analysis ◽  
Scanning Electron

Over the past decades, the combination of energy-dispersive analysis of X-rays and scanning electron microscopy has proved to be a powerful tool for fast and reliable elemental characterization of a large variety of specimens. The technique has evolved rapidly from a purely qualitative characterization method to a reliable quantitative way of analysis. In the last 5 years, an increasing need for automation is observed, whereby energy-dispersive analysers control the beam and stage movement of the scanning electron microscope in order to collect digital X-ray images and perform unattended point analysis over multiple locations.The Philips High-speed Analysis of X-rays system (PHAX-Scan) makes use of the high performance dual-processor structure of the EDAX PV9900 analyser and the databus structure of the Philips series 500 scanning electron microscope to provide a highly automated, user-friendly and extremely fast microanalysis system. The software that runs on the hardware described above was specifically designed to provide the ultimate attainable speed on the system.

PENGGUNAAN TiO2 PARTIKEL NANO HASIL SINTESIS BERBASIS AIR MENGGUNAKAN METODA SOL-GEL PADA BAHAN KAPAS SEBAGAI APLIKASI UNTUK TEKSTIL ANTI UV

Arena Tekstil ◽  
2013 ◽  
Vol 28 (1) ◽  
Author(s):  
Maya Komalasari ◽  
Bambang Sunendar
Keyword(s):  
Fourier Transform ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Sol Gel ◽  
Crosslinking Agent ◽  
X Ray Diffraction ◽  
Nano Tio2 ◽  
X Ray ◽  
Infra Red ◽  
Scanning Electron

Partikel nano TiO2 berbasis air dengan pH basa telah berhasil disintesis dengan menggunakan metode sol-gel dan diimobilisasi pada kain kapas dengan menggunakan kitosan sebagai zat pengikat silang. Sintesis dilakukan  dengan prekursor TiCl4 pada konsentrasi 0,3 M, 0,5 M dan 1 M, dan menggunakan templat kanji dengan proses kalsinasi pada suhu 500˚C selama 2 jam. Partikel nano TiO2 diaplikasikan ke kain kapas dengan metoda pad-dry-cure dan menggunakan kitosan sebagai crosslinking agent. Berdasarkan hasil Scanning Electron Microscope (SEM),diketahui bahwa morfologi partikel TiO2 berbentuk spherical dengan ukuran nano (kurang dari 100 nm). Karakterisasi X-Ray Diffraction (XRD) menunjukkan adanya tiga tipe struktur kristal utama, yaitu (100), (101) dan (102) dengan fasa kristal yang terbentuk adalah anatase dan rutile. Pada karakterisasi menggunakan SEM terhadap serbuk dari TiO2 yang telah diaplikasikan ke permukaan kain kapas, terlihat adanya imobilisasi partikel nano TiO2 melalui ikatan hidrogen silang dengan kitosan pada kain kapas. Hasil analisa tersebut kemudian dikonfirmasi dengan FTIR (Fourier Transform Infra Red) yang hasilnya memperlihatkan puncak serapan pada bilangan gelombang 3495 cm-1, 2546 cm-1, dan 511 cm-1,  yang masing-masing diasumsikan sebagai adanya vibrasi gugus fungsi O-H, N-H dan Ti-O-Ti. Hasil SEM menunjukkan pula bahwa kristal nano yang terbentuk diantaranya adalah fasa rutile , yang berdasarkan literatur terbukti dapatberfungsi sebagai anti UV.

Failure Analysis of Killer Defects and Yield Enhancement of Flat ROM Devices in Wafer Fabrication

2000 ◽  
Author(s):  
Y. N. Hua ◽  
Z. R. Guo ◽  
L. H. An ◽  
Shailesh Redkar
Keyword(s):  
Electron Microscope ◽  
Failure Analysis ◽  
Fault Isolation ◽  
Yield Enhancement ◽  
Wafer Fabrication ◽  
X Ray ◽  
Particle Contamination ◽  
Emission Microscopy ◽  
Microscopy Techniques ◽  
Scanning Electron

Abstract In this paper, some low yield cases in Flat ROM device (0.45 and 0.6 µm) were investigated. To find killer defects and particle contamination, KLA, bitmap and emission microscopy techniques were used in fault isolation. Reactive ion etching (RIE) and chemical delayering, 155 Wright Etch, BN+ Etch and scanning electron microscope (SEM) were used for identification and inspection of defects. In addition, energy-dispersive X-ray microanalysis (EDX) was used to determine the composition of the particle or contamination. During failure analysis, seven kinds of killer defects and three killer particles were found in Flat ROM devices. The possible root causes, mechanisms and elimination solutions of these killer defects/particles were also discussed.

scholarly journals Influence of the Nb and V Addition on the Microstructure and Corrosion Resistance of the Fe-B-Co-Si Alloy

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4045
Author(s):  
Rafał Mech ◽  
Jolanta Gąsiorek ◽  
Amadeusz Łaszcz ◽  
Bartosz Babiarczuk
Keyword(s):  
Corrosion Resistance ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Significant Influence ◽  
Corrosion Performance ◽  
X Ray ◽  
Final Performance ◽  
Differential Calorimeter ◽  
Comparison Of The Results ◽  
Scanning Electron

The paper presents a comparison of the results of the corrosion resistance for three Fe-B-Co-Si-based newly developed alloys with the addition of Nb and V. The corrosion performance differences and microstructure variations were systematically studied using scanning electron microscope, electric corrosion equipment, X-ray diffractometer, and differential calorimeter. It has been shown that each alloying addition increased the corrosion resistance. The highest corrosion resistance obtained by potentiodynamic polarization was found for the alloy with both Nb and V addons (Fe57Co10B20Si5Nb4V4) and lowest in the case of the basic four-element Fe62Co15B14Si9 material. This shows that the proper choice of additions is of significant influence on the final performance of the alloy and allows tailoring of the material for specific applications.

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