Synthesis, infrared stealth and corrosion resistance of organically modified silicate–polyaniline/carbon black hybrid coatings

AbstractOrganically-modified silicate (Ormosil) films have been found to provide good corrosion resistance for metal substrates and are potential replacement systems for hexavalent chromiumbased conversion coatings. Significant enhancement in corrosion resistance properties were observed upon addition of sub-micron to micron-sized particles (TiO2, Al2O3, SiN, TiN) to the Ormosil coating as determined using accelerated salt spray and electrochemical analysis. Rcorr values derived from potentiodynamic polarization curves were found to increase from 1520 to (3800 - 4680) kΩcm2 upon addition of various concentrations of TiO2, Al2O3, SiN or TiN particles to the Ormosil thin film. Similarly, Epit values were found to range from +0.2 V for the non-doped Ormosil to (0.6 – 1.9) V for particle-doped Ormosil thin films.

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Carbon nanotube-reinforced siloxane-PMMA hybrid coatings with high corrosion resistance

Progress in Organic Coatings ◽

10.1016/j.porgcoat.2012.11.015 ◽

2013 ◽

Vol 76 (4) ◽

pp. 601-608 ◽

Cited By ~ 40

Author(s):

P. Hammer ◽

F.C. dos Santos ◽

B.M. Cerrutti ◽

S.H. Pulcinelli ◽

C.V. Santilli

Keyword(s):

Corrosion Resistance ◽

Carbon Nanotube ◽

Hybrid Coatings ◽

High Corrosion Resistance ◽

High Corrosion

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Effect of cerium concentration on microstructure, morphology and corrosion resistance of cerium–silica hybrid coatings on magnesium alloy AZ91D

Progress in Organic Coatings ◽

10.1016/j.porgcoat.2010.05.004 ◽

2010 ◽

Vol 69 (1) ◽

pp. 52-56 ◽

Cited By ~ 33

Author(s):

Xiankang Zhong ◽

Qing Li ◽

Junying Hu ◽

Xiaokui Yang ◽

Fei Luo ◽

...

Keyword(s):

Corrosion Resistance ◽

Magnesium Alloy ◽

Hybrid Coatings ◽

Alloy Az91d ◽

Microstructure Morphology ◽

Silica Hybrid

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Comparison of Structure and Properties of the PVD, Hybrid (Galvanic + PVD), and Galvanic Coatings Deposited onto the Brass Substrate

Materials Science Forum ◽

10.4028/www.scientific.net/msf.591-593.860 ◽

2008 ◽

Vol 591-593 ◽

pp. 860-864 ◽

Cited By ~ 1

Author(s):

Leszek Adam Dobrzański ◽

Krzysztof Lukaszkowicz

Keyword(s):

Mechanical Properties ◽

Corrosion Resistance ◽

Hard Coatings ◽

Hybrid Coatings ◽

Metallographic Analysis ◽

Pvd Coatings ◽

Nitride Coatings ◽

Naoh Solution ◽

Erosion Test ◽

Made In

The properties of thin hard coatings and consequently their functionality are influenced by microstructural characteristics such as mechanical properties. A variety of interlayers has been used in hybrid coatings for various purposes. The paper presents investigation results of the structure, erosion and corrosion resistance, and mechanical properties of the galvanic Ni/Cr, hybrid Ni/Cr + Zr/ZrN (galvanic + PVD) and monolithic nitride coatings deposited by PVD technique (dc magnetron sputtering) onto brass (CuZn40Pb2) substrates. The ceramic PVD coatings or layers are the Cr-, Ti-, TiAl-, Zr-nitrides. The investigation covered the metallographic analysis on the scanning electron microscope, mechanical properties and erosion test. The corrosion tests were made in a 1 M NaOH solution. It was found out that PVD coatings display high corrosion resistance.

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Evaluation of Corrosion Resistance in 3.5% NaCl Solution of Hybrid Coatings Obtained from Plastics Materials

Materiale Plastice ◽

10.37358/mp.21.1.5459 ◽

2021 ◽

Vol 58 (1) ◽

pp. 201-209

Author(s):

Alina Crina Muresan ◽

Daniela Laura Buruiana ◽

Gabriel Bogdan Carp ◽

Sorin Berbece ◽

Constantin Trus

Keyword(s):

Corrosion Resistance ◽

Corrosion Rate ◽

Disperse Phase ◽

Phenol Formaldehyde ◽

Corrosion Current ◽

Phenol Formaldehyde Resin ◽

Hybrid Coatings ◽

Formaldehyde Resin ◽

Nacl Solution ◽

Plastic Materials

In this work, the corrosion resistance of hybrid coatings obtained from plastic materials was evaluated and compared with the corrosion resistance of Zn coatings. Zinc and hybrid coatings were obtained by electrodeposition from zinc sulphate electrolyte. For obtained hybrid coatings it was used as disperse phase two type of plastic materials: phenol-formaldehyde resin and epoxy resin. Polarization was used to measure the corrosion rate and behaviour of zinc and hybrid coatings in 3.5% NaCl solution. Tafel curves show that the including particles of plastic materials in zinc matrix disturbs the cathodic reactions and reduces anodic reaction leading to decrease of corrosion current and increase the corrosion resistance of hybrid coatings obtained at the same electrodeposition parameters as zinc coatings. Smallest values of corrosion rate were evaluated for hybrid coatings obtained with phenol-formaldehyde resin as disperse phase that indicates a good corrosion resistance in 3.5% NaCl solution.

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Enhancing Conductivity and Corrosion Resistance by Organic Coatings on AZ31 Magnesium Alloy Treated by Micro-Arc Oxidation

Volume 2: Processes; Materials ◽

10.1115/msec2019-2894 ◽

2019 ◽

Author(s):

Xiuping Zhang ◽

Lei Li ◽

Yaozhao Mu ◽

Yanxiang Xie ◽

Jun Dai ◽

...

Keyword(s):

Electrical Conductivity ◽

Corrosion Resistance ◽

Magnesium Alloy ◽

Carbon Black ◽

Composite Coatings ◽

Electrochemical Corrosion ◽

Organic Coating ◽

Organic Coatings ◽

Micro Arc Oxidation ◽

Conductive Particles

Abstract In this study, an organic coating, in combination of a micro-arc oxidation ceramic layer, was prepared on the surface of a magnesium alloy (AZ31) to achieve both functions of corrosion resistance and electrical conductivity. By using carbon black as conductive particles and epoxy resin as matrix, organic coatings of various weight fractions were applied on the AZ31 surface treated by micro-arc oxidation through adjusting the contents of the conductive particles and non-conductive matrix. Electrical conductivity and corrosion resistance of organic coatings were measured. The results show that the organic coatings can improve the electrical conductivity of the AZ31 material treated by micro-arc oxidation, and the conductivity changes with the ratio between the carbon black particles and non-conductive matrix. The smallest resistance value of the organic coatings reached 130Ω. Also, the organic coating can further improve the corrosion resistance of the AZ31 material. The electrochemical corrosion tests show that the corrosion potential of the AZ31 material with composite coatings was at least 0.6V higher than that of AZ31 only with micro-arc oxidation treatment.

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Effect of Carbon Black Content and Molding Pressure on the Thermal Conductivity of SiC/Si Ceramic Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.655.58 ◽

2015 ◽

Vol 655 ◽

pp. 58-61

Author(s):

Qi Song Li ◽

Yu Jun Zhang ◽

Hai Bin Sun ◽

Yan Xia Zhai ◽

Chao He

Keyword(s):

Thermal Conductivity ◽

Corrosion Resistance ◽

Heat Exchanger ◽

Carbon Black ◽

Room Temperature ◽

Ceramic Composites ◽

Molding Pressure ◽

Carbon Black Content ◽

Promising Candidate ◽

Infiltration Technique

SiC/Si ceramic composites have been considered as promising candidate materials for heat exchanger due to their good thermal conductivity and corrosion resistance. In this work, the SiC/Si ceramic composites were fabricated by liquid silicon infiltration technique, and the effect of carbon black content and molding pressure on thermal conductivity of the composites was studied. With carbon black content increasing from 5 wt. % to 25 wt. %, the thermal conductivity increased from 42.36 W/(m·K) to 65.60 W/(m·K) when molding pressure was fixed as 50 MPa. With molding pressure increasing from 30 MPa to 110 MPa, the thermal conductivity of SiC/Si ceramic composites with 20 wt. % carbon black content increased firstly, and then decreased, obtaining a maximum thermal conductivity of 71.62 W/(m·K) under 90 MPa. The SiC/Si ceramic composites with an optimal thermal conductivity of 76.55 W/(m·K) at room temperature were obtained when carbon black content and molding pressure were 25 wt. %, 90 MPa, respectively.

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