Salt Spray Resistance Research Articles

Preparation and Properties of Waterborne Acrylic-Modified Epoxy Phosphate Resin and Its Coating

An acrylic acid-modified epoxy phosphate resin coating was synthesized by a four-step method marked “A-B-C-D”, and it was used as an efficient protective layer for steel structures. The coating exhibited good properties, mainly including water resistance (≥240 h), salt spray resistance (≥300 h), surface drying time (≤1 h), and adhesion (≥6.5 MPa).

Preparation of Silicone Coating and Its Anti-Ice and Anti-Corrosion Properties

To enhance protection against corrosion and ice on iron metal material in frigid zones, an organic silicone resin coating was prepared using four monomers. Its structure and performance was analyzed via infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), and thermal analysis (TG). Corrosion resistance of coating was tested by saltwater resistance and salt spray resistance and assessed using an electrochemical workstation, alongside anti-icing tests. The results showed that the organic silicone resin was successfully synthesized. The coatings could delay freezing onset by one-third compared to controls in low temperatures, with a detachment time also reduced by one-third, indicating excellent corrosion and ice resistance. The methylphenyl silicone resin had good anti-corrosion and anti-ice properties, with a low corrosion current density (icorr) of 0.8793 μA/cm2 and a high charge transfer resistance (Rct) of 24,930 Ω·cm2 in saline.

Review and Future Prospects of Properties and Applications of Graphene based Anti corrosion Composite Materials

This article reviews the properties and application prospects of graphene based anti-corrosion composite materials in the field of anti-corrosion. This article mainly introduces the preparation methods and property testing results of composite materials such as graphene/polyaniline, graphene oxide/aluminum tripolyphosphate, and silica graphene oxide. Through hardness, impact resistance, electrochemistry, and salt spray resistance tests, the superiority of graphene based composite materials over individual anti-corrosion coatings has been revealed. The future outlook is on how to change the current situation, improve anti-corrosion effects, and point out the development direction of composite materials. This review aims to provide reference for the research of graphene anti-corrosion composite materials and promote their application in the field of anti-corrosion coatings.

Synthesis of a waterborne epoxy curing agent based on polyether triols and its application in 2K waterborne epoxy coatings

AbstractPolyether polyols can improve the performance of waterborne epoxy curing agent. In this paper, intermediates were synthesized from polyether triols with epoxy resin E‐51 and introduced into the epoxy curing agent by reacting with TETA. This paper focuses on the process of synthesizing the intermediates. The 2K waterborne epoxy coating film prepared with polyether triols‐modified waterborne epoxy curing agent exhibits desirable corrosion protection capacity and neutral salt spray resistance up to 600 h. In addition, the 2K waterborne epoxy coating film prepared using the modified waterborne epoxy curing agent with polyether triols displayed improved surface appearance, mechanical properties, and water resistance.

Study on the protective performance of coating system for thermal spraying zinc on radar

In response to the harsh marine environment protection needs of radar, the protective performance of 9 types of coating systems for thermal spraying zinc was studied through condensation tests, salt spray tests, and temperature tests. The blistering phenomenon of the radar thermal spraying zinc matching protective coating system was analyzed. The research results showed that the blistering of the thermal spraying zinc matching protective coating system may be related to the pores of the sealing coating. Among the 9 coating systems, the comprehensive performance of B and D coating systems in terms of moisture resistance, salt spray resistance, and temperature stress resistance is significantly superior to other coatings. The radar using B and D coating systems has been successfully applied to various types of harsh marine environments, improving the radar’s protective performance.

Fabrication and electrochemical properties of bonded NdFeB magnetic rings coated with double layer epoxy resin coating

On bonded NdFeB magnetic rings (B/NdFeB), a double-layer epoxy resin (DL-EP) coating was created using rolling spraying and cathode electrophoretic deposition techniques. The corrosion behaviors of the B/NdFeB and coated samples were examined using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), high pressure accelerated aging test (PCT), and neutral salt spray resistance test (NSS). The DL-EP coating significantly improved the corrosion resistance of B/NdFeB, as evidenced by the comparison of corrosion current density (Jcorr), PCT time, and NSS time.

Assess the Possibility to Substituting Crude Oil-based Film Formers in Automotive Epoxy Metal Primers with Coconut oil-derived Bio-based Polyurethane Film Formers

There is a potential risk that diminishing some islands in the world map within a short time period due to global warming unless people divert into new strategies to use crude oil sustainability or replace with renewable resources. Polyurethane (PU) is one of the most popular film-forming materials in the coating industry because of its better performance. A coconut oil-derived biobased polyol (BBP) was synthesized and acid value, viscosity, reaction water release, oil length, FTIR spectrum, differential scanning calorimetry and Lovibond colourimetric index were assessed during the synthesis. A series of pigmented renewable polyurethane metal primer (RPUMP) wet samples were prepared by using BBP under two categories as direct-to-metal (DTM) primers and undercoat primers (UCP) in two mixing ratios with polyisocyanate hardener as 2:1 and 4:1. All samples were comparatively tested with crude oil born commercially available epoxy metal (CAEMP) primers in Sri Lankan market for apparent viscosity, fineness of grinding, solid content, specific gravity, gloss, drying time, hardness, dry film thickness, adhesion, impact resistance, water resistance, salt spray resistance and cylindrical mandrel bending. According to the results, it was proven that RPUMP showed overall better performances with the corresponded CAEMP under the DTM category. But under the UCP category RPUMP showed better performances in apparent viscosity, drying time and water resistance but equal magnitude for pencil hardness. CAEMP showed better performances in solid content, specific gravity, dry film thickness, flexibility, impact resistance and salt spray resistance.

Salt Spray Resistance of Roller-Compacted Concrete with Surface Coatings.

In order to evaluate the feasibility of surface coatings in improving the performance of RCC under salt spray conditions, sodium silicate (SS), isooctyl triethoxy silane (IOTS), and polyurea (PUA) were used as surface coatings to prepare four types of roller-compacted concrete (RCC): reference RCC, RCC-SS, RCC-IOTS, and RCC-PUA. A 5% sodium sulfate solution was used to simulate a corrosive marine environment with high temperatures, high humidity, and high concentrations of salt spray. This study focuses on investigating various properties, including water absorption, abrasion loss, compressive strength, dynamic elastic modulus, and impact resistance. Compared to the reference RCC, the 24 h water absorption of RCC-SS, RCC-IOTS, and RCC-PUA without salt spray exposure decreased by 22.8%, 77.2%, and 89.8%, respectively. After 300 cycles of salt spray, the abrasion loss of RCC-SS, RCC-IOTS, and RCC-PUA reduced by 0.3%, 4.4%, and 34.3%, respectively. Additionally, their compressive strengths increased by 3.8%, 0.89%, and 0.22%, and the total absorbed energy at fracture increased by 64.8%, 53.2%, and 50.1%, respectively. The results of the study may provide a reference for the selection of coating materials under conditions similar to those in this study.

Lubrication, wear resistance and corrosion protection on aluminum alloy toward multifunctional coatings with nano-CeO2 inhibition effect

The coupling effect of wear and corrosion aggravates the damage and failure of key moving parts of high-end equipment, leading to a significant reduction in their service life. In present work, a functional integrated composite coating with exceptional corrosion resistance and tribological properties was developed by utilizing the responsive corrosion inhibition of nano‑cerium oxide (nano-CeO2) and the low surface energy and low shear characteristics of polytetrafluoroethylene (PTFE). The tribological behaviors and corrosion protection performance of coatings on aluminum alloy 2024 were evaluated and the corrosion inhibition mechanism was further discussed. The results revealed that Ce3+ on the surface of nano-CeO2 reacts with OH− generated by the REDOX reaction of the cathode to produce a uniform and stable passivation film, which can effectively improve the corrosion resistance of the metal matrix. Notably, the most obvious passivation effect is presented when the 2 % addition of nano-CeO2 as the larger low-frequency impedance modulus of 4.49 × 1010 Ω·cm2 and higher phase angle of 88°. The introduction of PTFE not only changes the coating from hydrophilic to hydrophobic, but also further improves the shielding properties of the coating. The low-frequency impedance modulus of the coating further increases by an order of magnitude to 2.38 × 1011 Ω·cm2, and its neutral salt spray resistance exceeds 210 days. Besides, the friction coefficient is reduced by 77.43 % and the wear resistance improved by 6.8 times compared with phenolic epoxy coating. Due to the enhancement and corrosion inhibition effect of nano-CeO2, the lower friction coefficient (0.044) and good wear resistance are further presented under the corrosive medium condition of 3.5 % NaCl solution.

Research on Nano-Titanium Modified Phenolic Resin Coating and Corrosion Resistance

Nano-titanium can be used in the field of anticorrosive coatings due to its excellent corrosion resistance. In this paper, phenolic resin was modified by nano-titanium using a physicochemical method. The nano-titanium-modified phenolic resin was used as a matrix to prepare the anticorrosive coating. The microstructures of the coatings were analyzed by Scanning Electron Microscope (SEM), X-ray spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR). Raman and UV spectrum adhesion of the coating was tested by a scratching method. The corrosion behavior was studied by electrochemical workstation and salt spray test. The results showed that the corrosion resistance of pure phenolic resin coating was significantly improved by the nano-titanium-modified phenolic resin. The coating containing 4% titanium nanoparticles exhibited the best corrosion resistance, with the highest impedance and the smallest corrosion current. The coating remained intact after 480 h of salt spray, showing the best salt spray resistance performance.

Studies of zinc content reduction using flake zinc powder in epoxy zinc-rich coatings

Purpose Epoxy zinc-rich coatings are widely used in harsh environments because of the long-lasting cathodic protection of steel surfaces. The purpose of this paper is to use flake zinc powder instead of the commonly used spherical zinc powder to reduce the zinc powder content. Design/methodology/approach In this paper, the authors have prepared an anticorrosive zinc-rich coating using a flake zinc powder instead of the conventional spherical zinc powder. The optimal dispersion of scaly zinc powder in zinc-rich coatings has been explored by looking at the surface and cross-sectional morphology and studying the cathodic protection time of the coating. Findings The final epoxy zinc-rich coating with 35 Wt.% flake zinc powder content was prepared using sand-milling dispersions. It has a similar cathodic protection time and salt spray resistance as the 60 Wt.% spherical zinc-rich coating, with a higher low-frequency impedance modulus value. Originality/value This study uses flake zinc powder instead of the traditional spherical zinc powder. This reduces the amount of zinc powder in the coating and improves the corrosion resistance of the coating.

Polysilazane Anti-corrosion Coating that Can Replace Hot-dip Galvanizing

In response to the problems of high energy consumption and pollution and insufficient anti-corrosion performance in the preparation process of hot-dip galvanized anti-corrosion materials, a polysilicon nitride anti-corrosion coating was developed. Using vinyl polysilazane as the base resin and adding zinc powder antirust pigment to the resin, a polysilazane zinc-rich anticorrosion coating was developed. The performance of the coating was characterized, and the results showed that the coating had a hardness of 6 H after heat treatment at 250°C and a salt spray resistance better than that of hot-dip zinc samples. 2000 h of salt spray resistance after heat treatment at 600°C, which is twice that of hot-dip galvanized materials, and the scratches are self-healing. The coating is a good substitute for hot-dip galvanized material.

Corrosion resistance of graphene/basalt flake modified waterborne epoxy zinc-rich primer

Purpose The purpose of this study is to evaluate the effect of graphene, basalt flakes and their synergy on the corrosion resistance of zinc-rich coatings. As the important heavy-duty anticorrosion coatings, zinc-rich coatings provided cathodic protection for the substrate. However, to ensure cathodic protection, a large number of zinc powder made the penetration resistance known as the weakness of zinc-rich coatings. Therefore, graphene and basalt flakes were introduced into zinc-rich coatings to coordinate its cathodic protection and shielding performance. Design/methodology/approach Three kinds of coatings were prepared; they were graphene modified zinc-rich coatings, basalt flakes modified zinc-rich coatings and graphene-basalt flakes modified zinc-rich coatings. The anticorrosion behavior of painted steel was studied by using the electrochemical impedance spectroscopy (EIS) technique in chloride solutions. The equivalent circuit methods were used for EIS analysis to obtain the electrode process structure of the coated steel system. Simultaneously, the corrosion resistance of the three coatings was evaluated by water resistance test, salt water resistance test and salt spray test. Findings The study found that the addition of a small amount of graphene and basalt flakes significantly improved the anticorrosion performance of coatings by enhancing their shielding ability against corrosive media and increasing the resistance of the electrochemical reaction. The modified coatings exhibited higher water resistance, salt water resistance and salt spray resistance. The graphene-basalt flakes modified zinc-rich coatings demonstrated the best anticorrosion effect. The presence of basalt scales and graphene oxide in the coatings significantly reduced the water content and slowed down the water penetration rate in the coatings, thus prolonging the coating life and improving anticorrosion effects. The modification of zinc-rich coatings with graphene and basalt flakes improved the utilization rate of zinc powder and the shielding property of coatings against corrosive media, thus strengthening the protective effect on steel structures and prolonging the service life of anticorrosion coatings. Originality/value The significance of developing graphene-basalt flakes modified zinc-rich coatings lies in their potential to offer superior performance in corrosive environments, leading to prolonged service life of metallic structures, reduced maintenance costs and a safer working environment. Furthermore, such coatings can be used in various industrial applications, including bridges, pipelines and offshore structures, among others.

Fluorine‐phosphate copolymerization waterborne acrylic resin coating with enhanced anticorrosive performance

AbstractThe modified waterborne acrylic resin was synthesized successfully by emulsion polymerization with octafluoropentyl methacrylate and phosphate functional monomer as monomers, showing an improved anti‐corrosion performance of the resin coating. The existence and general distribution of the elements of the modified monomer in the emulsion were explored, and the anti‐corrosion mechanism was disclosed. The results show that the modification of octafluoropentyl methacrylate and phosphate functional monomers improved the water resistance, corrosion resistance and thermal stability of acrylic resins. Compared with unmodified acrylic resin, the contact angle of the modified resin was increased from 74.23° to 83.51°, and the initial decomposition temperature was increased from 264 to 305 °C. At the same time, the corrosion voltage of the modified resin was increased, the corrosion current density was decreased, and the salt spray resistance was improved. This study provides a new way for the preparation of environmentally friendly, stable, and corrosion‐resistant waterborne acrylic resins.

Improved Salt Spray Resistance of Silver-Plated SiO2 via Self-Assembled Mercapto Inhibitors

Highly conductive fillers are an essential raw material in the fabrication of conductive composites, paste, ink, adhesive, etc. Still, susceptibility to salt spray erosion remains a serious issue for silver-based fillers. Herein, we first prepared highly conductive silver-plated microspherical silica (Ag/pSiO2) through catechol/polyamine surface functionalization and subsequently formed a self-assembled inhibition layer on the surface of Ag/pSiO2 by using (3-mercaptopropyl)trimethoxysilane (KH590) to enhance the salt spray erosion resistance. The results suggested that the self-assembled KH590 greatly improved the salt spray erosion resistance of the Ag/pSiO2. The total shielding effectiveness (SEt) of the composites protected by KH590 was 106 dB after the salt spray erosion, which was even 16 dB higher than that before erosion. In contrast, the SEt of the composites without KH590 decreased significantly from 111 to 76 dB. Further studies revealed that the KH590 inhibitor strongly prevented the penetration of Cl– and subsequently enhanced the salt spray resistance. Considering the facile and effective preparation, this strategy could be applied in large-scale silver-based EMI shielding materials.

Fabricating polyethylene(PE) films on magnesium alloy by RF-PECVD for the corrosion protection of electronic products

The poor corrosion resistance of Mg alloy has limited its application in 3C (computer, communication, consumer electronics) electronic products. The ultra-thin and fluorine-free of films is urgently needed to protect electronic products. In this work, fluorine-free Polyethylene (PE) and crosslinked-Polyethylene (C-PE) films were prepared by PECVD method for the protection of Mg alloy electronic products. The PE film is uniform and dense and the introduction of the crosslinker improves the uniformity and density of the film. The corrosion protection performance of C-PE film is further improved compared with PE film. Salt spray results show that the salt spray resistance time of C-PE film with 1.56 μm thickness reaches 72 h. The addition of the crosslinker endows the film with a denser structure and blocks the intrusion of corrosive media, making the C-PE film have excellent corrosion resistance.

Structural Design and Analysis of an Airborne Equipment

The airborne electronic equipment has high requirements in high temperature resistance, vibration resistance, humidity and heat resistance and salt spray resistance, and the technical indexes of heat dissipation, vibration resistance and three-proof performance are determined through reliability analysis and the working characteristics of the components themselves. This paper introduces the design process of an airborne electronic equipment structure scheme. Under the conditions of meeting the structural size requirements and three-proof performance, the mainframe and antenna structure scheme is designed by analyzing the heat generation and vibration resistance requirements of components, and the temperature and mechanical simulation is verified by using ANSYS software. The design scheme meets the requirements of environmental adaptability.

High-temperature deformation characteristics of 3D printing of nano-ceramic materials

In order to improve the application effect of three-dimensional printing of nano ceramic materials, the high-temperature deformation characteristics of three-dimensional printing of nano ceramic materials were studied. First, the main raw materials and experimental instruments for preparing nano ceramic materials were selected. Then, high-temperature nano ceramic materials were prepared by using 8%, 12%, and 15% polyester modified silicone resins respectively; And put it into the storage box of the direct writing 3D printer to print the 3D ceramic sample with the 3D printer. At last, the high temperature deformation characteristics under different high temperature environments are analysed. The results show that the adhesive force and salt spray resistance of 12% polyester modified silicone resin 3D ceramic specimens are good, and the bending strength of 12% polyester modified silicone resin 3D ceramic specimen is high, its structural stability is good, and the deformation value is small under the same high temperature environment.

Development of Waterborne Heavy-Duty Anticorrosive Coatings with Modified Nanoscale Titania

The steel structures of coastal engineering in the moist tropics and subtropics are always under a C5/CX level corrosion environment with high temperature, high humidity, and high salt fog. Anticorrosive waterborne coatings with high weatherability and reliability are urgently to be developed. In this work, one kind of waterborne heavy-duty anticorrosive coatings, with the advantages of excellent corrosion resistance, self-repairing ability, self-cleaning ability, and high film compactness, was successfully achieved through modifying the side chains on the surface morphologies of the spherical nanoscale titania. The micromorphology and structure of the coating were characterized by a scanning electron microscope (SEM), transmission electron microscope (TEM), and atomic force microscope (AFM). The anticorrosion characteristics and forming mechanism of the modified nanoscale titania coating were analyzed. The salt spray tests showed that the neutral salt spray resistance time of the modified nanoscale titania coating was 1440 h. Its durability reached the H level and met the design requirements for 15 years of anticorrosion lifetime. The modified nanoscale titania coatings had been large-scale commercially applied at some typical steel structures under an extreme harsh corrosion environment in one coastal thermal power plant. The results showed that no rusting, peeling, or crack phenomena were observed after 3 years of service under different harsh coastal corrosion conditions.

Study on Modified Liquid Polysulfide Rubber Bimetallic Salt-Spray-Resistant Epoxy Coatings

In this study, liquid polysulfide rubber was modified by silane coupling agent. New kinds of anti-corrosion coatings with salt spray resistance and strong adhesion to the steel substrate were obtained using the modified liquid polysulfide rubber, bimetallic filler, carbon nanotubes, and epoxy resin. Infrared and nuclear magnetic resonance confirmed the preparation of new modified liquid polysulfide rubber through coupling reaction between the epoxy group of silane compound and the sulfide group of the liquid polysulfide rubber. A 1440 h neutral salt spray test showed the coating to be completely free of rust and blisters. The corrosion diffusion width of the scribed area was only 1.7 mm. In addition, in a 3.5% by weight NaCl solution, the coating shows no blistering and no corrosion phenomena compared with zinc-rich epoxy paints (the added zinc content was only 28.6%). These tests confirmed that the new coating had a dense microstructure, strong adhesion to the steel substrate, good corrosion resistance, and anti-blister performance. The performance indicates that the coatings have potential for use in the atmosphere and underwater, which provides a better choice for long-term protection of marine projects such as ships, wharves, offshore platforms, and wind power structures.