Comparative studies of microstructural, tribological and corrosion properties of Zn-TiO2 and Zn-TiO2-WO3 nano-composite coatings

Abstract Nano composite coatings on HSLA ASTM A860 alloy, adds to the barrier efficacy by increase in the microhardness, wear and corrosion resistance of the substrate material. Additionally, reduction of delamination of the nano composite coating sample is ascertained. Ball milling is availed to curtail the coating samples (Al2O3/ZrO2) to nano size, for forming a electrodeposited product on the substrate layer. The curtailment in grain size was ascertained to be 17.62% in Ni-Al2O3/ZrO2 nano composite coating. During the deposition process, due to the presence of Al2O3/ZrO2 nano particles an increase in cathode efficiency is ascertained. An XRD analysis of the nano composite coating indicates a curtailment in grain size along with increase in the nucleation sites causing a surge in the growth of nano coating layer. In correlation to uncoated HSLA ASTM A36 alloy sample, a surge in compressive residual stress by 47.14%, reduction of waviness by 32.14% (AFM analysis), upsurge in microhardness by 67.77% is ascertained in Ni-Al2O3/ZrO2 nano composite coating. Furthermore, in nano coated Ni-Al2O3/ZrO2 composite a reduction is observed pertaining to weight loss and friction coefficients by 27.44% and 13% in correlation to plain uncoated alloy respectively. A morphology analysis after nano coating indicates, Ni-Al2O3/ZrO2 particles occupy the areas of micro holes, reducing the wide gaps and crevice points inside the matrix of the substrate, enacting as a physical barrier to upsurge the corrosion resistance by 67.72% in correlation to HSLA ASTM A860 base alloy.

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Composite Coatings Formed on PEO Pretreated MA8 Magnesium Alloy in Aqueous Suspension of PTFE

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.885.95 ◽

2021 ◽

Vol 885 ◽

pp. 95-102

Author(s):

Evgeny A. Belov ◽

Konstantine V. Nadaraia ◽

Dmitry V. Mashtalyar ◽

Igor M. Imshinetsky ◽

Andrey P. German ◽

...

Keyword(s):

Composite Coatings ◽

Aqueous Suspension ◽

Corrosion Current ◽

Composite Polymer ◽

Corrosion Properties ◽

Composite Layers ◽

Electrolytic Oxidation ◽

Subsequent Application ◽

Plasma Electrolytic ◽

Scratch Tests

The paper presents results of the composite polymer-containing layers formation by plasma electrolytic oxidation (PEO) with subsequent application of the superdispersed polytetrafluoroethylene (SPTFE) aqueous suspension. The corrosion properties and adhesion of coatings have been investigated using potentiodynamic polarization and scratch tests. Incorporation of SPTFE decreased the corrosion current density for composite layers by more than 3 orders of magnitude in comparison with the base PEO-coating and increased the coatings adhesion by 30 %.

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Mechanical properties and corrosion behaviour after scratch and tribological tests of electrodeposited Co-Mo/TiO2 nano-composite coatings

Applied Surface Science ◽

10.1016/j.apsusc.2018.12.099 ◽

2019 ◽

Vol 475 ◽

pp. 162-174 ◽

Cited By ~ 7

Author(s):

H. Krawiec ◽

V. Vignal ◽

A. Krystianiak ◽

Y. Gaillard ◽

S. Zimowski

Keyword(s):

Mechanical Properties ◽

Corrosion Behaviour ◽

Composite Coatings ◽

Nano Composite ◽

Tribological Tests ◽

Mechanical Properties And Corrosion

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Features of CЕС technology for eco- and energytechnologies

Bulletin of the National Technical University «KhPI» Series New solutions in modern technologies ◽

10.20998/2413-4295.2021.03.13 ◽

2021 ◽

pp. 89-96

Author(s):

Mykola Sakhnenko ◽

Hanna Karakurkchi ◽

Tetiana Nenastina ◽

Irina Yermolenko ◽

Alla Korohodska

Keyword(s):

Technological Process ◽

Composite Coatings ◽

Functional Materials ◽

Modular Approach ◽

Properties Of Coatings ◽

Corrosion Properties ◽

Energy Characteristics ◽

Flexible Control ◽

Energy Technologies ◽

Time And Energy

Based on the analysis of the peculiarities of CEC formation, it is shown that their production and application is one of the world trends in functional electroplating and allows to solve a number of practical problems, in particular in the field of eco- and energy technologies. The deposition of polyfunctional CECs of cobalt with refractory metals was carried out from citrate-pyrophosphate electrolytes in galvanostatic and pulsed modes. The obtained composite coatings have a complex of increased mechanical and anti-corrosion properties, catalytic and photocatalytic activity, which determines the prospects for the use of the obtained thin-film materials in many industries. It is shown that the processes of formation of such multicomponent systems are very complex, a separate problem that needs to be solved is the organization of the technological process of CEC adapted to production needs. The scheme of organization of technological process on the basis of the modular approach which is based on results of complex researches of influence of quantitative characteristics of working electrolytes and modes of electrolysis on structure and properties of the synthesized coverings is developed. The generalized scheme of CEC technology reflects the sequence of generally accepted processes and operations in electrochemical production with the possibility of applying the modular principle of organization of galvanic sites and shops. Variability of technological schemes provides flexible control of the composition and properties of coatings by changing the time and energy characteristics of electrodeposition with insignificant adjustment of the quantitative and qualitative composition of electrolytes. The developed modular approach in the organization of technological process can be used as a basis for other electrochemical technologies of synthesis of functional materials.

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