Study of Hillock and Zinc Whisker Evolution in Five Different Cable Tray Coatings

The main objective of this work is the study of the hillock and zinc whisker evolution of five different commercial zinc coatings applied on the same base steel wires of the patented EASYCONNECT system cable trays manufactured by VALDINOX Ltd.: white zinc alkaline electrolyte, yellow zinc trivalent electrolyte, acid zinc electrolyte, hot dip galvanized, and zinc nickel coating. The limited literature on the subject is summarized, and then the coating thickness, chemical composition, hardness and surface rugosity are characterized. The hillock and whisker density evolution are evaluated over a period of 12 months, considering the presence of compression bending stresses. It is concluded that the white alkaline and yellow trivalent coatings are the most affected, while the zinc-nickel shows the best behavior with no presence of whiskers; the acid zinc electrolyte also shows good results despite the delayed appearance of whiskers from the ninth month; the hot-dip galvanized coating does not show any presence of zinc whiskers or hillocks.

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Possibilities of Utilization of Waste Materials in Production of Electrically Conductive Composites on Silicate Basis

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.321.171 ◽

2021 ◽

Vol 321 ◽

pp. 171-176

Author(s):

Jana Majerová ◽

Rostislav Drochytka

Keyword(s):

Nickel Powder ◽

Cement Composite ◽

Wire Drawing ◽

Waste Materials ◽

Electrically Conductive ◽

Conductive Composites ◽

Steel Wires ◽

The Subject ◽

Conductive Properties ◽

Functional Fillers

The electrical conductivity of concrete can be achieved by adding steel wires or functional fillers. Commonly used fillers are nanotubes, carbon black, nickel powder and so on. These fillers are expensive, but there is a possibility to use waste materials. This is the subject of this experiment. The conductive properties of conductive sand, sludge from the wire drawing process, iron grinding dust waste and waste carbon were verified. From these fillers, waste carbon showed the best electrical properties (impedance). The impedance of the waste carbon was 0.31 Ω and the impedance of the cement composite containing 70% of the weight of waste carbon was less than 670 Ω.

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Study of Microstructure and Corrosion Resistance of Zinc Electrodeposits before and after Black Chromating

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.751.119 ◽

2017 ◽

Vol 751 ◽

pp. 119-124

Author(s):

Kanokwan Saengkiettiyut ◽

Pranee Rattanawaleedirojn ◽

Adisak Thueploy ◽

Jumpot Wanichsampan ◽

Yuttanant Boonyongmaneerat

Keyword(s):

Corrosion Resistance ◽

Electrochemical Impedance ◽

Salt Spray ◽

Alkaline Electrolyte ◽

Corrosion Properties ◽

Electrochemical Testing ◽

Before And After ◽

Coat Layer ◽

Zinc Coatings ◽

Salt Spray Testing

In this work, microstructure and corrosion properties of zinc electroplated steel before and after black chromating was investigated. The test samples were prepared by electrodeposition process, using a commercially-available alkaline electrolyte. Subsequently, the galvanized samples were applied with a black chromate-based passivation layer and a clear top-coat layer. Their microstructures were examined using X-ray diffractometry and scanning electron microscopy. The corrosion resistance of the samples was assessed with the salt spray test, following the ASTM B117, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization in 5 wt.% NaCl solutions. The study showed that zinc electroplated steels exhibit (110) crystallographic orientation. The passivation and top-coat layers did not affect the microstructure of the zinc layer, and covered uniformly on the zinc layer for all sets of samples. The corrosion resistant results obtained from salt spray testing and electrochemical testing revealed that the microstructure of zinc coatings prepared by using different applied current did not influence on their corrosion resistance markedly. While black passivation followed by top coating provided a significant improvement on corrosion resistance of the coatings.

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Gamma Phase Zinc Nickel Electrodeposits from Alkaline Electrolyte

10.4271/2005-01-0543 ◽

2005 ◽

Author(s):

Craig V. Bishop ◽

Agnes Rousseau ◽

Vince Opaskar ◽

Lee Capper ◽

Roland Vogel

Keyword(s):

Alkaline Electrolyte ◽

Gamma Phase ◽

Nickel Electrodeposits ◽

Zinc Nickel

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The Determination of Friction Coefficient between Parallel Wires in Stay Cables

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.351-352.250 ◽

2013 ◽

Vol 351-352 ◽

pp. 250-253 ◽

Cited By ~ 1

Author(s):

Hong Li

Keyword(s):

Friction Coefficient ◽

High Strength Steel ◽

Steel Wire ◽

High Strength ◽

Pressure Increase ◽

Positive Pressure ◽

Stay Cables ◽

Steel Wires ◽

Bending Stresses

To measure and determine the friction coefficients of steel wires accurately is one of the prerequisite for analysing the local bending stresses in staycables. Three test schemes to simulate the real working state of the steel wire, the test value and its variation trend shows that the friction coefficient of high-strength steel wires decreases with the pressure increase, and then becomes stable when the positive pressure is too large.

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Protection of fuel filter with alkaline and acid zinc coatings

Glasnik hemicara i tehnologa Bosne i Hercegovine ◽

10.35666/ghtbh.2019.53.01 ◽

2019 ◽

pp. 1-8

Author(s):

Jelena Scepanovic ◽

Safija Herenda ◽

Fehim Korac ◽

Darko Vuksanovic ◽

Dragan Radonjic

Keyword(s):

Corrosion Resistance ◽

Base Material ◽

Alkaline Electrolyte ◽

Electrochemical Tests ◽

Tafel Polarization ◽

Aesthetic Appearance ◽

Fuel Filter ◽

Corrosion Zone ◽

Zinc Coatings

Galvanic coatings are applied so that the surface of the base material obtains appropriate properties, corrosion resistance, durability, aesthetic appearance, and long-term application in the appropriate industry. In this paper, the aim was to protect steel fuel filters with alkaline and acid zinc coatings of different thicknesses. The coating of zinc, which is applied from the alkaline electrolyte, provides good corrosion protection with excellent coating flexibility. The thickness of the coating by the X-ray fluorescence method was tested, followed by coating tests, corrosion resistance, and electrochemical tests. The results of adhesion showed a high quality coating, as no corrosion occurred during the test. The corrosion resistance tested by the salt chamber method speaks of the appearance of white and red corrosion. On alkaline electrolyte coatings, white corrosion occurred after 168 hours of exposure to the salt test, while on white zinc samples there was a white corrosion after 240 hours of exposure. Tafel polarization diagrams have been determined: corrosion potentials, current intensities, anode and cathode Tafel coefficients and calculated corrosion rates. The active and passive corrosion zone is determined by the cyclic voltammetry.

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