Characterization of Surface Roughness

2000 ◽  
Vol 6 (S2) ◽  
pp. 916-917
Author(s):  
John C. Russ

Because of the session at this Microscopy and Microanalysis 2000 meeting concerned with the microanalysis of irregular surfaces, it seems appropriate to briefly review the methods used for the characterization of rough surfaces. This includes both mathematical tools for the concise description of surface roughness, and instruments used to acquire the necessary data. These methods are widely used in industry to characterize and specify the roughness of surfaces prepared by various machining, grinding, polishing, chemical etching, and physical and chemical deposition techniques, and to correlate the surface roughness with performance.Historically, surface roughness has been measured by performing a linear traverse with a mechanical stylus that is sensitive to vertical displacements of nm but with a lateral resolution on the order of pm, which is quite similar to the dimensions of the region analyzed by X-ray microanalysis. Recently, more comprehensive characterizations have been obtained using a raster scan over surface areas.

Author(s):  
C. Goessens ◽  
D. Schryvers ◽  
J. Van Landuyt ◽  
A. Verbeeck ◽  
R. De Keyzer

Silver halide grains (AgX, X=Cl,Br,I) are commonly recognized as important entities in photographic applications. Depending on the preparation specifications one can grow cubic, octahedral, tabular a.o. morphologies, each with its own physical and chemical characteristics. In the present study crystallographic defects introduced by the mixing of 5-20% iodide in a growing AgBr tabular grain are investigated. X-ray diffractometry reveals the existence of a homogeneous Ag(Br1-xIx) region, expected to be formed around the AgBr kernel. In fig. 1 a two-beam BF image, taken at T≈100 K to diminish radiation damage, of a triangular tabular grain is presented, clearly showing defect contrast fringes along four of the six directions; the remaining two sides show similar contrast under relevant diffraction conditions. The width of the central defect free region corresponds with the pure AgBr kernel grown before the mixing with I. The thickness of a given grain lies between 0.15 and 0.3 μm: as indicated in fig. 2 triangular (resp. hexagonal) grains exhibit an uneven (resp. even) number of twin interfaces (i.e., between + and - twin variants) parallel with the (111) surfaces. The thickness of the grains and the existence of the twin variants was confirmed from CTEM images of perpendicular cuts.


2012 ◽  
Vol 730-732 ◽  
pp. 569-574
Author(s):  
Marta Cabral ◽  
Fernanda Margarido ◽  
Carlos A. Nogueira

Spent Ni-MH batteries are not considered too dangerous for the environment, but they have a considerable economical value due to the chemical composition of electrodes which are highly concentrated in metals. The present work aimed at the physical and chemical characterisation of spent cylindrical and thin prismatic Ni-MH batteries, contributing for a better definition of the recycling process of these spent products. The electrode materials correspond to more than 50% of the batteries weight and contain essentially nickel and rare earths (RE), and other secondary elements (Co, Mn, Al). The remaining components are the steel parts from the external case and supporting grids (near 30%) containing Fe and Ni, and the plastic components (<10%). Elemental quantitative analysis showed that the electrodes are highly concentrated in metals. Phase identification by X-ray powder diffraction combined with chemical analysis and leaching experiments allowed advancing the electrode materials composition. The cathode is essentially constituted by 6% metallic Ni, 66% Ni(OH)2, 4.3% Co(OH)2 and the anode consists mainly in 62% RENi5 and 17% of substitutes and/or additives such as Co, Mn and Al.


2012 ◽  
Vol 730-732 ◽  
pp. 9-14 ◽  
Author(s):  
Bruno Henriques ◽  
Filipe Silva ◽  
Delfim Soares

The purpose of this work was to perform a chemical and mechanical characterization of a preoxidized CoCrMo alumina blasted surface. This is a commonly performed surface treatment used in metal-porcelain systems for dental restorations to remove oxides formed during preoxidation heat treatment from the metal’s surface. CoCrMo dental alloy’s specimens produced by lost wax process were examined in terms of chemical composition using X-Ray fluorescence spectroscopy (XRF), Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS); in terms of mechanical characteristics through the means of a microhardness test and in terms of surface roughness using a profilometer. It was investigated the chemical composition of various surface conditions: non-preoxidized, preoxidized, ground oxidized surface and sandblasted oxidized surface. After alumina blasting, the oxides level on metal’s surface remained high. Alumina blasting treatment (Ø110 µm) produced an 84% increase of CoCrMo surface hardening and an increase in surface roughness (Ra=0.58 µm). It was found alumina contaminants on the metal’s surface. Therefore, it was concluded that alumina blasting do not entirely removes the oxide layer formed during preoxidation heat treatment. It produced a chemical and mechanical surface modification that can influence the metal-ceramic bond strength.


2021 ◽  
Vol 16 (1) ◽  
pp. 199-210
Author(s):  
Máté Karlik ◽  
◽  
Ildikó GYOLLAI ◽  
Anna VANCSIK ◽  
Krisztián FINTOR ◽  
...  

The catchment (bedrock and soil) and sediments of lake Bolătău, Romania were studied by high resolution multi-methodological investigations to characterize paleoenvironmental and formation conditions. Particle size analyses, optical and cathodoluminescence microscopy, FTIR-ATR and Raman spectroscopy, X-ray powder diffraction, and XRF were applied for microtextural, chemical, micro-mineralogical and embedded organic material characterization and distribution of the sediments, especially concerning geochemical conditions, like pH and redox potential change. Our results support physical and chemical weathering in the process of soil formation with appearance of the new minerals appear (10Å sized phyllosilicates and clay minerals). Comparison of these studies offer possible differentiation of syn- and diagenetic mineralization, the clarification of debris contribution, microbial mediation and complex mineralization via decomposition of cell and extracellular polymeric substance. Based on the analyses on the abrasives, a suboxic environment prevailed in the depositional area and considerable microbial contribution is proposed via accumulation of lake sediments.


2019 ◽  
Vol 942 ◽  
pp. 40-49
Author(s):  
Yulia Murashkina ◽  
Olga B. Nazarenko

Natural zeolite of Shivirtui deposit (Russia) was modified with nanofibers of aluminum oxyhydroxide AlOOH. Aluminum oxyhydroxide nanofibers were produced at the heating and oxidation of aluminum powder with water. The properties of modified zeolite were investigated by means of X-ray diffraction, transmission electronic microscopy, scanning electronic microscopy, low-temperature nitrogen adsorption, thermal analysis, and Fourier transform infrared spectroscopy. It was found that water content in the modified sample of zeolite was about 15 %. Based on the study of the physical and chemical properties, shivirtui zeolite modified with nanofibers of aluminum oxyhydroxide can be proposed for use as a flame-retardant additive to polymers.


1997 ◽  
Vol 3 (S2) ◽  
pp. 1247-1248
Author(s):  
R. M. Fisher ◽  
J. Holbery ◽  
Barbara Reine

A major problem now hampering increased recycling of old cardboard containers (OCC), is the presence of significant amounts of polymeric materials such as adhesives, tapes, labels and wax which enter the pulp process stream along with the cardboard and paper that was collected for recycling. Many of these materials contain very fine particles of inorganic fillers and pigments. These various contaminant constituents combine in some, as yet unknown, manner to form an extremely gummy material that deposits on paper machine surfaces and sticks tenaciously (hence the term “Stickies”). The sticky blobs are very difficult to remove and increases machine downtime and maintenance costs as well as causing blemishes on the finished container board product Light optical image analysis, UV fluorescence, FTIR and electron microscopy are being used in consort with particle size measuring instruments, TGS and DSC thermal analysis techniques, FTIR infra-red spectroscopy as well as XRF (x-ray fluorescence spectroscopy ), XPS (x-ray photo emission spectroscopy) and classical contact angle determination methods as part of a broad program to characterize the physical and chemical nature of stickies in pulp slurries with the goal of removing them or alleviating their pronounced tendency to deposit on machinery and paper products.


2014 ◽  
Vol 979 ◽  
pp. 440-443
Author(s):  
W. Siriprom ◽  
K. Teanchai ◽  
S. Kongsriprapan ◽  
J. Kaewkhao ◽  
N. Sangwaranatee

The chemical and physical properties of topsoil and subsoil which collected from the cassava cropping area in Chonburi Province have been investigated. The characterization of both soil sample were used X-Ray Diffraction (XRD), Energy Dispersive X-Ray Fluorescence (EDXRF) while FTIR used to confirmed the formation of intermolecular bonding and Thermo-Gravimetric Analysis (TGA) used for investigated the crystalline. It was found that, the XRD pattern indicated quartz phase. The chemical composition by XRF reported that the soils samples consist of Si, Al, Ca, Fe, K, Mn, Ti, Cr, Zn, Ag and Cu. and TGA results, noticed that the removal of moisture and organics material.


2020 ◽  
pp. 096739112092169
Author(s):  
Asmaa Bouazza ◽  
Salah Bassaid ◽  
Bouabdallah Daho ◽  
Massimo Messori ◽  
Abdelkader Dehbi

The aim of this work is to study some physical and chemical properties of an organic semiconductor (OSc)/ x%titanium dioxide (TiO2) heterosystem (with 0 ≤ x ≤ 20%) (OScs/ x%TiO2). The OSc is obtained from pure curcumin and paracetamol as starting molecules. The synthesis methodology of the mixtures of OScs/ x%TiO2 heterosystem involves a microwave-assisted multicomponent reaction using curcumin, paracetamol, and TiO2 as a heterogeneous solution. All mixtures were analyzed by Fourier-transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis/differential thermal analysis, X-ray diffraction, ultraviolet–visible spectroscopy, and scanning electron microscopy. The results obtained show a new nanocomposite with interesting pharmaceutical, optical, electronic, and structural properties, which can be used in the fields of energy production, water purification, and air purification, as a biomaterial and for electronic applications.


Author(s):  
Yootaek Kim

Four low-index surfaces; (A-surface), (0001) (basal surface), (R-surface), and of the α-Al203 single crystals were investigated by reflection electron microscopy (REM) and reflection high energy electron diffraction (RHEED) techniques[1] and the characteristics of these surfaces are reported. Specimens were prepared by polishing and annealing[2, 3], Orientation of each surface was confirmed with x-ray diffraction using a Laue camera. Microscopy observation was carried out on a JEOL JEM-200CX TEM operated at 100 KV.To facilitate a fair comparison, the surface areas which were obviously affected by a macroscopic tilt, localized contamination, etc., were avoided. Only the flat, clean, and smooth areas were compared. The surface (Fig. 1. The scale in this figure also applies to all other figures.) shows large atomically flat areas divided by steps running in <000 1> and directions. The steps in this image are not of the same height. Some are one or two atoms high and others are much higher. Fig. 2 shows the surface which is periodically facetted. One type of the facets is flat and atomically smooth while the other type is rough. The (0001) planes display curved and/or straight steps[4]. An example of curved step configuration is shown in Fig. 3. Most of the steps in this image have the same height. This step configuration is similar to the surface shown in Fig. 4. However, the contrast of the steps are very different; on the (0001) surfaces the steps are much darker and well-defined. A summary of these four surfaces is presented in the table below.


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