Restoration of drying cylinders on spinning machines by gas detonation spraying

Abstract The structure and mechanical properties of the coatings formed by reactive detonation spraying of titanium in a wide range of spraying conditions were studied. The variable deposition parameters were the nature of the carrier gas, the spraying distance, the O2/C2H2 ratio, and the volume of the explosive mixture. The phase composition of the coatings and the influence of the spraying parameters on the mechanical properties of the coatings were investigated. In addition, nanohardness of the individual phases contained the coatings was evaluated. It was found that the composition of the strengthening phases in the coatings depends on the O2/C2H2 ratio and the nature of the carrier gas. Detonation spraying conditions ensuring the formation of composite coatings with a set of improved mechanical properties are discussed.

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Features of the Formation of Various Functional Coatings of SHS Mechanical Composites Using Gas Detonation Spraying Technology

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.299.879 ◽

2020 ◽

Vol 299 ◽

pp. 879-886

Author(s):

Aleksei V. Sobachkin ◽

A.A. Sitnikov

Keyword(s):

Raw Materials ◽

Micro Hardness ◽

Coating Properties ◽

Functional Coatings ◽

Detonation Spraying ◽

Gas Detonation ◽

X Ray ◽

Gas Detonation Spraying ◽

Mechanical Composites

The present work is devoted to the determination of the characteristics of the deposition of coatings for various areas of technology, using the technology of gas detonation spraying of powder SHS mechanical composites. In the work, the most rational modes of coating deposition were determined, macro-and microstructures, surface topography, as well as coating properties (antifriction, micro-hardness, wear resistance) were investigated, and energy dispersion and X-ray phase analysis of raw materials and gas detonation coatings were carried out.

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Creation of Bioceramic Coatings on the Surface of Ti–6Al–4V Alloy by Plasma Electrolytic Oxidation Followed by Gas Detonation Spraying

Coatings ◽

10.3390/coatings11121433 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1433

Author(s):

Bauyrzhan Rakhadilov ◽

Daryn Baizhan

Keyword(s):

Titanium Alloy ◽

Phase Composition ◽

Plasma Electrolytic Oxidation ◽

Chemical Compositions ◽

Detonation Spraying ◽

Gas Detonation ◽

Electrolytic Oxidation ◽

Plasma Electrolytic ◽

Gas Detonation Spraying ◽

Bioceramic Coatings

In this work, bioceramic coatings were formed on Ti6Al4V titanium alloy using a combined technique of plasma electrolytic oxidation followed by gas detonation spraying of calcium phosphate ceramics, based on hydroxyapatite. Plasma electrolytic oxidation was carried out in electrolytes with various chemical compositions, and the effect of electrolytes on the macro and microstructure, pore size and phase composition of coatings was estimated. Three types of electrolytes based on sodium compounds were used: phosphate, hydroxide, and silicate. Plasma electrolytic oxidation of the Ti–6Al–4V titanium alloy was carried out at a fixed DC voltage (270 V) for 5 min. The sample morphology and phase composition were studied with a scanning electron microscope and an X-ray diffractometer. According to the results, the most homogeneous structure with lower porousness and many crystalline anatase phases was obtained in the coating prepared in the silicate-based electrolyte. A hydroxyapatite layer was obtained on the surface of the oxide layer using detonation spraying. It was determined that the appearance of α-tricalcium phosphate phases is characteristic for detonation spraying of hydroxyapatite, but the hydroxyapatite phase is retained in the coating composition. Raman spectroscopy results indicate that hydroxyapatite is the main phase in the coatings.

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