Analysis on Microstructure of Laser Brazing Diamond Grits with a Ni-Based Filler Alloy

Brazing diamond grits onto steel substrate using a Ni-based filler alloy was carried out via laser beam in an argon atmosphere. The microstructure of the interfacial region among the Diamond grits and the filler layer were investigated by means of scanning electron microscopes (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS). Meanwhile, the formation mechanism of carbide layers was discussed. All the results indicated that the active element chromium in the Ni-based alloy concentrated preferentially to the surface of the grits to form a chromium-rich layer, and the hard joint between the alloy and the steel substrate is established through a cross-diffusion of iron and Ni-based alloy through parameters optimization.

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Laser Brazing of Diamond Grits with a Ni-Based Brazing Alloy

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.359-360.43 ◽

2007 ◽

Vol 359-360 ◽

pp. 43-47 ◽

Cited By ~ 7

Author(s):

Zhi Bo Yang ◽

Jiu Hua Xu ◽

Yu Can Fu ◽

Hong Jun Xu

Keyword(s):

Active Element ◽

Steel Substrate ◽

Interfacial Region ◽

X Ray Diffraction ◽

Laser Brazing ◽

X Ray ◽

Cross Diffusion ◽

Filler Layer ◽

Electron Microscopes ◽

Scanning Electron Microscopes

Brazing diamond grits onto steel substrate using a Ni-based filler alloy was carried out by laser beam in an argon atmosphere. The microstructure of the interfacial region among the Diamond grits, the filler layer and the steel substrate, were investigated by means of scanning electron microscopes (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS). Meanwhile, the formation mechanism of carbide layers was discussed. All the results indicated that the active element chromium in the Ni-based alloy concentrated preferentially to the surface of the grits to form a chromium-rich layer, and the hard joint between the alloy and the steel substrate is established through a cross-diffusion of iron and Ni-based alloy.

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Preparation and properties of nanocrystalline Ni/graphene composite coatings deposited by electrochemical method

Polish Journal of Chemical Technology ◽

10.2478/pjct-2018-0005 ◽

2018 ◽

Vol 20 (1) ◽

pp. 29-34 ◽

Cited By ~ 3

Author(s):

Grzegorz Cieślak ◽

Maria Trzaska

Keyword(s):

Steel Substrate ◽

Composite Coatings ◽

X Ray Diffraction ◽

Dispersion Phase ◽

X Ray ◽

Graphene Layers ◽

Nano Crystalline ◽

Graphene Flakes ◽

Electron Microscopes ◽

Scanning Electron Microscopes

Abstract The paper presents results of studies of composite nickel/graphene coatings produced by electrodeposition method on a steel substrate. The method of producing composite coatings with nanocrystalline nickel matrix and dispersion phase in the form of graphene is presented. For comparative purposes, the study also includes nano-crystalline Ni coatings produced by electrochemical reduction without built-in graphene flakes. Graphene was characterized by Raman spectroscopy, transmission and scanning electron microscopes. Results of studies on the structure and morphology of Ni and Ni/graphene layers produced in a bath containing different amounts of graphene are presented. Material of the coatings was characterized by SEM, light microscopy, X-ray diffraction. The microhardness of the coatings was examined by Knoop measurements. The adhesion of the coatings with the substrate was tested using a scratchtester. The influence of graphene on the structure and properties of composite coatings deposited from a bath with different graphene contents was determined.

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Otosclerotic Stapes: Morphological and Microchemical Correlates

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348947708600413 ◽

1977 ◽

Vol 86 (4) ◽

pp. 525-540 ◽

Cited By ~ 21

Author(s):

David J. Lim ◽

William H. Saunders

Keyword(s):

Calcium Salt ◽

Mineral Deposit ◽

Ground Substance ◽

X Ray Diffraction ◽

Typical Pattern ◽

X Ray ◽

Initial Stage ◽

Electron Microscopes ◽

Sclerotic Lesions ◽

Scanning Electron Microscopes

A total of 32 otosclerotic stapes is thin-sectioned without decalcification and examined using transmission and scanning electron microscopes, with a nondispersive x-ray analyzer attached to the latter. These otosclerotic stapes are classified as spongiotic, sclerotic, or preotosclerotic, according to their pathologic characteristics and state of mineralization. Either diffuse or patchy demineralization in the ground substance appears to be the initial stage of otosclerosis, and this area coincides with preotosclerotic lesions (also known as blue mantle) in light microscopy. Therefore, it is interpreted that demineralization precedes the destruction of ground substance in the preotosclerotic lesion. Bone mineral deposits in new otosclerotic bone appear to be related to the collagen fibrils that are embedded in the ground substance. No mineral deposit could be seen without the ground substance deposition; therefore, it is suggested that this ground substance is the single most important factor in the poor mineralization of the otosclerosis. The sclerotic lesions are well mineralized and show a typical pattern of hydroxyapatite by x-ray diffraction study. We could not confirm the notion that the sclerotic lesion is hypermineralized as compared to the normal stapes. The spongiotic lesions are poorly mineralized, with low calcium salt. Using the Ca/P ratio and x-ray diffraction pattern as criteria, it was determined that spongiotic lesions belong to unstable, immature bone.

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Thermodynamic Analysis of Interfacial Reaction between Diamond and Ni-Cr Alloys

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.42.440 ◽

2010 ◽

Vol 42 ◽

pp. 440-443

Author(s):

Zhi Bo Yang ◽

Gui Bin Zhang ◽

Jiu Hua Xu

Keyword(s):

Interfacial Reaction ◽

Thermodynamic Analysis ◽

Steel Substrate ◽

High Strength ◽

Thermodynamic Theory ◽

Argon Atmosphere ◽

Filler Alloy ◽

X Ray Diffraction ◽

X Ray ◽

Energy Dispersion Spectrometer

Brazing diamond grits to steel substrate using Ni-based filler alloy was carried out via laser in an argon atmosphere. Thermodynamic analysis was performed in order to research the interfacial reaction mechanism of diamond and Ni-Cr alloy during high temperature brazing. Meanwhile, microstructure of the interfacial layer was experimentally detected by scanning electron microscope (SEM), energy dispersion spectrometer (EDS) and X-ray diffraction (XRD) in this paper. The results indicate that according to the thermodynamic theory the interfacial reaction has been proved feasible, and during brazing high strength bonding between diamond grits and the steel substrate has been successfully realized because the chromium in the Ni-based alloy segregated preferentially to the surface of the diamond to form a chromium-rich reaction product Cr3C2, and the bond between the alloy and the Diamond was established through the reaction product.

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Laser Welding of AISI 316 Steel: Microstructural and Stress Analysis

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4024155 ◽

2013 ◽

Vol 135 (3) ◽

Cited By ~ 11

Author(s):

B. S. Yilbas ◽

Sohail Akhtar

Keyword(s):

Residual Stress ◽

Base Material ◽

Element Model ◽

X Ray Diffraction ◽

X Ray ◽

Cooling Period ◽

Thermal Stress Field ◽

Electron Microscopes ◽

Aisi 316 ◽

Scanning Electron Microscopes

Thermal-stress field in the welded region was modeled incorporating the finite element model. Temperature and stress fields were predicted at different cooling periods. The morphological and metallurgical changes in the welded region were examined using optical and scanning electron microscopes, energy dispersive spectroscopy and X-ray diffraction. The residual stress formed at the surface vicinity of the weld was determined using the X-ray diffraction technique. It was found that the residual stress predicted agreed well with the experimental data. The solidification cracking did not occur in the weld section during the cooling period. The microhardness in the weld cross-section was almost 1.4 times the base material hardness.

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Failure Analysis of the Pressure Vessel by Stainless Steel: 1Cr18Ni9Ti

Journal of Pressure Vessel Technology ◽

10.1115/1.1811106 ◽

2004 ◽

Vol 126 (4) ◽

pp. 414-418 ◽

Cited By ~ 1

Author(s):

Junbo Zhou ◽

Kuisheng Wang ◽

Liping Gao

Keyword(s):

Stainless Steel ◽

Pressure Vessel ◽

Electrochemical Corrosion ◽

Chloride Ions ◽

X Ray Diffraction ◽

Corrosion Failure ◽

X Ray ◽

Electron Microscopes ◽

Scanning Electron Microscopes ◽

Welding Position

The corrosion failure of 1Cr18Ni9Ti stainless steel pressure vessel was studied with the aid of metallurgical microscopes, scanning electron microscopes, scanning Auger energy spectra and X-ray diffraction meters. The main causes of the failure included: inter-crystalline corrosion initiated at or near welding position between head and body of cylinder, electrochemical corrosion due to chloride ions in electrolyte and corrosive action formed by oxygen separator and hydrogen separator. Some measures of corrosion resistance and design improvement were proposed.

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The Scanning Electron Microscope As A Precision Instrument

Microscopy Today ◽

10.1017/s1551929500060909 ◽

1996 ◽

Vol 4 (6) ◽

pp. 30-34

Author(s):

Douglas Hansen

Keyword(s):

Diffraction Gratings ◽

Stray Field ◽

X Ray Diffraction ◽

Precision Instrument ◽

X Ray ◽

Electron Microscopes ◽

Scanning Electron Microscopes ◽

The University ◽

Straight Lines ◽

Scanning Electron

I began using scanning electron microscopes to solve problems encountered in the fabrication of x-ray diffraction gratings. Since these diffraction gratings consist of very regular lines and spaces, and produce high contrast images from the SEM. my microscopy work often points out problems with the microscope.One time, for example, I went to the university SEM lab I often use, and was advised that the microscope was down that day due to major field problems. This lab often had problems with stray fields for reasons no one could explain. Usually I was the only one to complain about stray field distortions since they are most obvious when imaging straight lines at high magnification, but on this occasion, the problem was serious and obvious to all.The microscope had just been serviced and as the lens coils had been replaced, they were expected to be the cause. The service technician was called in and determined that neither the coils nor the microscope electronics were the problem.

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Synthesizing of Zeolite Particle Using Alkaline Plant Extract

Emerging Advances in Integrated Technology ◽

10.30880/emait.2021.02.01.001 ◽

2021 ◽

Vol 02 (01) ◽

Author(s):

Tijjani Abdullahi ◽

◽

Zawati Harun ◽

Norsuhailizah Sazali ◽

Nur Hanis Hayati Hairom ◽

...

Keyword(s):

Plant Extract ◽

Fine Powder ◽

Secondary Phases ◽

X Ray Diffraction ◽

X Ray ◽

Zeolite Particle ◽

Naoh Solution ◽

Good Grade ◽

Electron Microscopes ◽

Scanning Electron Microscopes

The study explored the hydrothermal synthesis of zeolite using kaolin clay precursor in the presence of three different solvents namely, garlic extract, watermelon extract and 2M NaOH solution, with the view of testing their efficacy and potency for green synthesis. Before the zeolitization, the kaolin precursor was activated at a temperature of 850°C to produce metakaolin. The crystallization was achieved in an oven at a temperature of 90°C for 12 hours. The final product is grounded to a fine powder and subsequently undergo testing and characterization via X-ray Diffraction (XRD) and Field Emission Scanning Electron Microscopes (FESEM) methods. The purity and grade of the synthesized products vary accordingly with the suitability of the reaction solvent. The synthesized product using a solvent of watermelon plant extract was able to produce zeolite LTA of a good grade. However, the presence of secondary phases informed the effect of the accompanied impurities that might originate from the kaolin precursor or the solvent. The result also portrays the possibility of obtaining a well crystalline zeolite from the Malaysian kaolin without using any structural directing agent or chemical solvents.

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The Possibility of Deposition of Diamond and DLC Coatings by PACVD Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.641.111 ◽

2015 ◽

Vol 641 ◽

pp. 111-115

Author(s):

Marek Poręba ◽

Paulina Zawadzka ◽

Maria Richert ◽

Jan Sieniawski ◽

Tomasz Strączek ◽

...

Keyword(s):

Steel Substrate ◽

Chemical Vapor ◽

Diamond Coatings ◽

X Ray Diffraction ◽

Dlc Coatings ◽

Electron Microscopes ◽

Scanning Electron Microscopes ◽

Spherical Grains

The Diamond like carbon (DLC) and diamond coatings were deposited on a steel substrate using plasma assisted chemical vapor deposition (PA CVD) method. The parameters of deposition were analyzed in relation to the effectiveness of the process and the quality of coatings. It was found that the DLC coatings formed only at specific conditions of temperature and pressure of precursor gases. The characterization of coatings were performed by Raman spectromicroscopy, X-ray diffraction and infrared spectromicroscopy which allowed us to recognize the dominant phases and the distribution of bonds inside the coatings. The chemical bonds such as sp2 C-C, sp3 CH3/CH2 and sp3 CH were found in microstructure coatings. The maps of distribution of bonds in the coatings were also prepared. Additionally, their microstructure was investigated by scanning electron microscopes which have revealed a spherical grains morphology of the coatings.

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