Abstract
The paper considers the influence of the substrate polarity on the preparation of samples from sols for examination by X-ray photoelectron spectroscopy and atomic force microscopy.
The paper studies poly(ethylene terephthalate) films modified in corona discharge. Surface topography and elastic properties of films dependence on the distance between needle and grounded substrate ...are obtained by atomic force microscopy.
The method of uncovering the interphase layer in the systems "iron-nanosized polymer film" obtained in a low-temperature plasma on iron from hydrocarbons was used. A method of interface layer ...uncovering based on electrochemical dissolution of the iron substrate was proposed, which allowed one to achieve a high rate of metal. Ammonium sulfate solution was used as an electrolyte. A method of interface layer uncovering based on electrochemical dissolution of the iron substrate was proposed in the work. This allowed one to achieve a high rate of metal dissolution and make it possible to control the composition of the dissolution product. Salt solution was used as an electrolyte. Interface layer studies were carried out using the AFM and XPS methods, which allowed establishing the relief and chemical composition of the interphase boundary, as well as the location on the interphase surface of the metal-containing phase. The application of a double-layer iron substrate consisting of a plate of 56Fe nonresonance isotope with a 57Fe ultrafine layer deposited on its surface allowed one to use the Mössbauer spectroscopy for investigation of the chemical state of iron atoms in the interfacial region of "iron-nanoscale polymer film" systems.
Annotation The purpose of this work was determination of the changes in surface properties of Polyamide-12 powder used in Selective Laser Sintering (SLS). The powders of original polyamide Duraform ...PAtm (3D Systems) were investigated. Also the powders remaining around the product after the sintering process were investigated. The difference in the chemical structure of the Polyamide-12 powder surface layers has been established. The reason is the increased content of oxygen-containing groups in the surface layers. To a greater extent, this difference was revealed for powders left after sintering and intended for reuse. Aliphatic chains are subject to oxidative degradation in the surface layers of the original powder. In the powder remaining after sintering, terminal carbonyl and amine groups are subject to oxidative degradation.
The X-ray photoelectron spectroscopy method has been used to study the alpha case formed on the surface of a titanium alloy during its casting into ceramic molds, based on a mixture of oxides of ...magnesium, silicon, calcium, and water glass, as a binder. It is established that the alpha case consists of mold metal oxides, titanium oxides and complex intermetallic compounds based on titanium and mold elements.
The XPS method has been used to study the chemical composition of the surface of sand forms based on magnesium oxide. The original and modified forms were investigated. Modification of the form was ...carried out by plasma deposition of a titanium coating on the inner surface. The surface of the initial form consists of the initial oxides and intermetallic compounds based on the elements of the form. In the surface layers of the modified form, TiO2 is the main titanium-containing compound, silicon titanates and intermetallic compounds based on the elements of the form and titanium are present.
Influence of the effect of electric arc titanium spraying on the inner surfaces of ceramic molds used for casting titanium was observed. Casting surface and cross-section were examined by electron ...microscopy with a probe microanalysis system and X-ray photoelectron spectroscopy. It was observed there is an "alpha case" on the casting surface. Its thickness and elemental composition varies through the casting surface.
Numerical or semianalytical solution of problems of structural mechanics of high dimensionality is computationally costly process in many cases. However, structural engineer does not normally face ...the task of obtaining a solution of the problem with high accuracy at all points of the considered domain occupied by the structure. As a rule, all subdomains that are potentially dangerous in terms of structural strength are well known in advance. Operational and variational formulations of boundary problems of structural mechanics with the use of method of extended domain are presented. After corresponding (finite element or finite difference) discretization and passage to governing equations considering problems are transformed to a multilevel space with the use of multilevel wavelet transform (discrete Haar basis is used). Special algorithms of averaging are presented.
Boundary layers of the mold used for castings from titanium have been investigated by the method of electron microscopy with a system of probe microanalysis. Migration both components of mold and ...additives of titanium alloy is established to the surface layers of the form.
Previously, we have investigated the formation of polymer films from heptane on the surface of a metal substrate in low-temperature plasma (
LTP
) by varying the mode and time of plasma treatment ...1–3. It was found that the formation of the films occurs in three stages, each being characterized by certain topography, chemical structure, and mechanical properties of the films. In the first stage, continuous films are formed that mimic the substrate topography, smoothing it. The films are homogeneous in their chemical structure, have a low hardness, high permeability, and hydrophilicity. In the second stage, the films grow via the formation of isolated macromolecular entities, “islets.” At the end of the second step, the entire surface of the films is covered by the islets, and the films have a maximum hardness, low permeability, and hydrophobicity. In the third stage, the polymer chains undergo degradation accompanied by the intense etching of the film, which manifest itself in a reduction of its thickness, smoothing of the topography, enhancement of permeability, and surface hydrophilicity. In this study, we examined the effect of the chain length of saturated hydrocarbon molecules on the chemical structure and morphology of the polymer films formed in low-temperature plasma.
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