The Influence of High Velocity Thermal Spraying Methods on Top Surface Topography of WC-Co Coatings

2015 ◽  
Vol 226 ◽  
pp. 149-154
Author(s):  
Hanna Myalska ◽  
Jakub Wieczorek ◽  
Krzysztof Szymański ◽  
Grzegorz Moskal

Characterization of top surfaces of WC-Co coatings obtained during deposition process of high velocity thermal spraying type was showed in this article. The feedstock powder was so called “superfine” powder of WC-17Co types produced by Inframat. In first part of article short characterization of powder was presented, especially characterization of it morphology including shape, internal microstructure and grain size description. The second part of article is dedicated to characterization of microstructure and topography of top surface of coatings deposited by two different methods of high velocity thermal spraying. In this case analysis of top-surface condition by scanning microscopy with chemical analysis in microareas was used and as well as a qualitative and quantitative analysis of topography of carbides surface by traditional non-contact and laser profilometry.

2014 ◽  
Vol 602-603 ◽  
pp. 142-145
Author(s):  
Su Li ◽  
Jun Shou Li ◽  
Fang Zhao ◽  
Ming Yuan Wang ◽  
Xiao Juan Wu

On the basis of magnesiothermy, with Mg powder, TiO2 powder and B2O3 powder as mixed reactants, relatively pure TiB2 powder was prepared by self-propagating high temperature synthesis (SHS) after leached in diluted hydrochloric acid with the suitable concentration. The product after leached was examined by XRD for qualitative and quantitative analysis, SEM for morphology analysis and infrared spectroscopy for transmittance analysis. It was found that diluted hydrochloric acid could decrease most of the impurities, and the proportion of TiB2 phase in the product is more than 99%, which was hexagonal shape crystal with the grain size of 200-300 nm. Compare with the infrared spectrogram of the middle infrared spectral region of the product of before and after acid pickling, it was found that the transmittance of TiB2 is extremely low in the range of 2000-4000 cm-1, which can be excellent infrared absorption material in the corresponding wave band.


2013 ◽  
Vol 197 ◽  
pp. 186-191 ◽  
Author(s):  
Aneta Gądek-Moszczak ◽  
Sabina Żmudka

The main goal of the study was working out the method of qualitative and quantitative analysis of the microstructure on 3D images of the polypropylene composites with Tuf (type of rock consisting volcanic ash) particles. Three types of composite were analyzed: with 10, 15 and 25% of Tuf. The standard morphological parameters were indicated that describes size, shape, and distribution of Tuf particles in the matrix. The morphological characterization of examined microstructure was compared with mechanical properties. The optimal from the point of mechanical properties composition of this composite were proposed.


2015 ◽  
Vol 27 (5) ◽  
pp. 493-499 ◽  
Author(s):  
Simona Rella ◽  
Cosimino Malitesta

AbstractQualitative and quantitative analysis of surface species on size-segregated atmospheric particulate collected in Antarctica during the 2010–11 summer was performed by X-ray photoelectron spectroscopy (XPS). This represents the first example of surface characterization of Antarctic aerosols. The size class with particle cut-off diameter of 3 μm was richest in terms of chemical elements. Peculiar findings of the application included detection of Ca (possibly surface-segregated) and surface enrichment of Mg. The determination of nitrate, ammonium and sulphate species on collection filters provides evidence for a possible advantage of XPS over more laborious techniques (e.g. ion chromatography). The presence of these species is in reasonable agreement with other recent reports from Antarctica.


2009 ◽  
Vol 79-82 ◽  
pp. 397-400
Author(s):  
Yu Ping Wu ◽  
Gai Ye Li

A NiCr/Cr3C2 composite coating with a thickness of approximately 200 m was deposited onto 1Cr18Ni9Ti stainless steel substrate by high-velocity oxy-fuel (HVOF) thermal spraying. Microstructure of the coating was characterized using X-ray diffraction(XRD), scanning electron microscopy(SEM) and transmission electron microscopy (TEM). The coating comprised a NiCr matrix and two types of carbides. The NiCr matrix was composed of an amorphous phase and nanocrystalline grain with a size of 10–50 nm. The microhardness of the coating was found to be 1200Hv, which is significantly greater than that of the stainless steel (1Cr18Ni9Ti) substrate (285 Hv).


2021 ◽  
Author(s):  
Yudong Guan ◽  
Min Zhang ◽  
Manasi Gaikwad ◽  
Hannah Voss ◽  
Ramin Fazel ◽  
...  

ABSTRACTThe characterization of glycoproteins, like erythropoietin, is challenging due to the structural micro- and macro-heterogeneity of the protein glycosylation. This study presents an in-depth strategy for glycosylation analysis of a first-generation erythropoietin (epoetin beta), including a developed top-down mass spectrometric workflow for N-glycan analysis, bottom-up mass spectrometric methods for site-specific N-glycosylation and a LC-MS approach for O-glycan identification. Permethylated N-glycans, peptides and enriched glycopeptides of erythropoietin were analyzed by nanoLC-MS/MS and de-N-glycosylated erythropoietin was measured by LC-MS, enabling the qualitative and quantitative analysis of glycosylation and different glycan modifications (e.g., phosphorylation and O-acetylation). Extending the coverage of our newly developed Python script to phosphorylated N-glycans enabled the identification of 140 N-glycan compositions (237 N-glycan structures) from erythropoietin. The site-specificity of N-glycans was revealed at glycopeptide level by pGlyco software using different proteases. In total, 215 N-glycan compositions were identified from N-glycan and glycopeptide analysis. Moreover, LC-MS analysis of de-N-glycosylated erythropoietin species identified two different O-glycan compositions, based on the mass shifts between non-O-glycosylated and O-glycosylated species. This integrated strategy allows the in-depth glycosylation analysis of a therapeutic glycoprotein to understand its pharmacological properties and improving the manufacturing processes.


The application of mass spectrometry to steroids has been extensively developed since its inception in 1956. Detailed studies based on pure steroids and their isotope labelled analogues have established the major pathways of fragmentation under electron impact. The resulting correlations have been of great value in the analytical characterization of steroids and their metabolites. The combination of mass spectrometry with gas chromatography is particularly powerful: the latter technique reduces the complexity of samples, and provides independent characterization by virtue of retention regularities. These features are essential for distinguishing many stereoisomeric or otherwise closely related steroids. Modifications of functional groups can augment the utility of mass spectrometry in qualitative and quantitative analysis. Derivatives may be chosen to alter fragmentation modes, or to produce informative shifts in ion masses within an essentially unchanged fragmentation pattern. Enhancement of molecular ion abundance is usually achievable with derivatives, or by means of milder ionization techniques such as chemical ionization.


Author(s):  
J.B. Posthill ◽  
R.P. Burns ◽  
R.A. Rudder ◽  
Y.H. Lee ◽  
R.J. Markunas ◽  
...  

Because of diamond’s wide band gap, high thermal conductivity, high breakdown voltage and high radiation resistance, there is a growing interest in developing diamond-based devices for several new and demanding electronic applications. In developing this technology, there are several new challenges to be overcome. Much of our effort has been directed at developing a diamond deposition process that will permit controlled, epitaxial growth. Also, because of cost and size considerations, it is mandatory that a non-native substrate be developed for heteroepitaxial nucleation and growth of diamond thin films. To this end, we are currently investigating the use of Ni single crystals on which different types of epitaxial metals are grown by molecular beam epitaxy (MBE) for lattice matching to diamond as well as surface chemistry modification. This contribution reports briefly on our microscopic observations that are integral to these endeavors.


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