Effect Of Protective Coatings Research Articles

Effect and mechanism of ionic liquid-polymer composite coating on enhancing hydrogen embrittlement resistance of X80 pipeline steel for hydrogen blended natural gas transportation

Blending hydrogen into existing natural gas pipelines is a cost-effective method for large-scale hydrogen transportation. However, high hydrogen ratios cause hydrogen embrittlement in pipeline steel, limiting transportation efficiency. Due to complex structures and harsh application conditions, existing coatings are difficult to apply on pipelines. To tackle such issues, we propose an ionic liquid-polymer composite coating using epoxy resin as coating substrate, based on the competitive adsorption of methane and hydrogen on pipeline steel. Ionic liquids with high methane selectivity were selected via quantum chemical calculation. The protective effect of coatings was characterized using hydrogen pre-charging constant strain tensile tests. Simulation and experimental results demonstrate that epoxy resin coatings reduce hydrogen embrittlement in X80 steel. Modified with selective CH4/H2 permeability ionic liquids, the epoxy resin coating enhances methane and hydrogen competitive adsorption on the steel surface, improving hydrogen embrittlement resistance. This novel coating offers a viable solution for achieving safe and high ratio hydrogen blended transportation in natural gas pipeline.

The Effect of a Coating on the Crystallization of Multicomponent Co-Based Amorphous Alloys

The effect of protective coatings on the crystallization of amorphous Co-based alloys was studied using the methods of X-ray diffraction, differential scanning calorimetry, and transmission electron microscopy. The crystallization of the amorphous alloys was studied on as-prepared samples, deformed samples, and deformed samples with a protective coating. After heat treatment, the fraction of the crystalline phase in the pre-deformed samples was higher than in the undeformed samples. When using a protective coating, the fraction of nanocrystals formed during heat treatment increased. The size of the crystals formed in deformed samples was smaller, and in the deformed samples with a protective coating, they were slightly larger than in the corresponding initial samples. The reasons for the differences in the formed structure in the amorphous alloys under study are discussed in terms of free volume.

Effect of Protective Coatings on Wooden Elements Exposed to a Small Ignition Initiator

This paper presents the results of monitoring the behaviour of selected wood species exposed to a small ignition initiator. We specifically aimed to investigate the effect of retardant coating on the combustion process of the wood species spruce (Picea abies), red spruce (Larix decidua), Scots pine (Pinus sylvestris), ash (Fraxinus excelsior L.), beech (Fagus sylvatica), and oak (Quercus robur) when exposed to a small initiator of ignition. At the same time, we studied the effect of different types of fungicidal agents (based on N-(3-aminopropyl)-N-dodecylpropane-1,3-diamine; alkyl (C12–16) dimethylbenzyl ammonium chloride or 3-iodo-prop-2-inylbutylcarbamate) on the effectiveness of a flame retardant (containing ferric phosphate) applied to the selected fungicide-treated wood samples. The experimentally obtained mass-loss and flame-spread results were statistically evaluated using the QtiPlot software program. A significant dependence of mass loss and surface flame spread on wood species was the primary focus. It was only confirmed for the surface-flame-spread variable. The dependence of the effect of fungicide treatment on the effectiveness of the selected retardant was confirmed. Fungicidal coatings with the active ingredient alkyl/benzyl (C12–16) dimethylbenzyl ammonium chloride indicated the lowest mass loss rate and flame spread for all wood samples.

Effect of Protective Coatings in Welded Constructions on Welding Stability and Electrode Metal Transfer into a Weld Pool in MMA

The paper presents data of experimental research into the importance of protective surface coatings in welded products for MMA stability; heat field distribution patterns on their surfaces, and structure and phase composition of the welded metal. The study has revealed that a protective surface coating in a welded item in MMA has a positive effect on shortcut duration, increasing it by 5-11 %, raising its formation and transformation time by 10-12 %; 15% dimensional increase of a welded metal grain is registered as well, and a heat impact zone expands by 25%.

Enhanced corrosion inhibition of aniline derivatives electropolymerized coatings on copper: Preparation, characterization and mechanism modeling

Nanostructured polyaniline (PANi), poly(N-ethylaniline) (PNEA) and their molybdate-doped coatings (PANi-Mo and PNEA-Mo) were electropolymerized on passivated copper surface via voltammetric cycles in oxalic acid solution. The coating structures were featured by morphological observation, attenuated total reflectance infrared spectra (ATR-IR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS); besides, anticorrosive performance of coatings was investigated for copper in 0.5 M H2SO4 solution through electrochemical and topographical measurements. ATR-IR and XRD results documented the occurrence of polymerization over copper surface, while the morphologies implied that the presence of ethyl and molybdate generated the extra increment in coating thickness. Owing to physical barrier of substituent and in-situ dissolving of molybdate, the corrosion of coated specimens was highly suppressed in H2SO4 solution. The protective effect of coatings followed the sequence of PNEA-Mo > PANi-Mo > PNEA > PANi with an inverse trend in porosity index. XPS analyses revealed that repeat units of polymer were in mixed state with predominantly oxidative type, which were inclined to parallelly deposit on copper surface with a strong anchoring strength. Molecular dynamics simulations well supported the configuration and forceful adhesion of polymers on Cu (1 1 1) plane, and indicated the favorable compatibility between polymer and dopant.

Effect of protective coatings on serviceability of aluminium alloys in environment of oil production

The effect of protective coatings on the wear resistance and corrosion resistance of the 2024 aluminium alloy used for the oil drill pipes producing is studied. The nature of the drill pipes damage made of aluminium alloys during operation is analyzed. The microstructure of the coatings, the electrochemical potential and corrosion rate of the 2024 aluminium alloy with and without coatings of various compositions are studied, and comparative analysis of the adhesion and wear resistance of coatings is performed. It is shown that tube billet made of 2024 alloy with сoating based on tungsten carbide has the highest range of service properties and can be used to effectively protect the surface of aluminium drill pipes during operation.

Исследование влияния повышенной влажности воздуха и сернистого газа на эффективность защитных покрытий

Исследование влияния повышенной влажности воздуха и сернистого газа на эффективность защитных покрытий

Effect of Protective Coatings on Frost Resistance of Concrete Structures in Northeast Coastal Areas

Dalian is located in the northeast coastal area, and the complex environment has caused severe freezing and thawing damage to the marine concrete. The experiment used polyurea, polyurethane, epoxy mortar to protect the concrete surface, and then carried out indoor rapid freeze-thaw test to analyze the effect of coating on the antifreeze performance of concrete. The concrete samples were subjected to mercury intrusion test before and after the freeze-thaw cycle to analyze the pore structure changes of the concrete before and after erosion. The test results show that the concrete covered by protective coating has a lower mass loss rate and a higher dynamic elastic modulus than the unprotected concrete, the order of anti-freezing performance of the protective coating from strong to weak is: epoxy mortar > polyurethane > polyurea. By isolating the concrete from the corrosive environment, the protective coating can delay the ingress of corrosive materials, slow the tendency of harmless pores in the concrete to multiple the harmful holes and harmful pores, improve the frost resistance of the concrete, and prolong the use of the concrete structure life.

Wood protective coatings based on fluorocarbosilane

The effectiveness of protective coatings based on 3-(2,2,3,3,4,4,5,5-octafluoropentyloxy)propyltriethoxysilane in the protection of wood surface from the effects of water was tested. No earlier attempts at using the mentioned fluorocarbosilane for the protection of wood have been reported in the literature. The coatings were deposited by the sol–gel method. As a result of the generation of chemical bonds between the wood surface and silane, a coating was produced that permanently increased the wood hydrophobicity. Fluorinated chains attached to the silicon atoms make an effective barrier preventing the access of water and limiting the effects of water on the wood surface.

Assessing the Effect of Protective Coatings on the Resistance of the Concrete Floor to the Abrasion

How to extend your lifetime before you start using it or more often during use is a matter for every investor. In this paper, we will try to assess whether the use of protective coatings on concrete floors has a positive effect on the service life. The referee in our case will be the highly abrasive test method Böhme, which determines abrasion resistance. For comparison, we chose coatings based on sodium silicate solution, ie water glass. The market for these protective coatings is very diverse, so we have chosen to select products of renowned and unknown producers in different price ranges to cover the widest possible market.

Effect of protective coatings on the water absorption and mechanical properties of 3D printed PLA

This work aims to study the influence of protective coatings on the water absorption and mechanical properties of 3D printed poly–lactic acid (PLA) parts. The PLA parts were fabricated with different levels of the 3D printing process parameters, aiming to define samples with distinct strength and ductility/toughness characteristics. Water absorption tests following the standard ASTM D570–98 were performed on uncoated and coated PLA specimens. The effectiveness of two protective coatings based on acrylic and polyurethane varnish on reducing water absorption was evaluated. Both protective coatings have shown being effective on preventing water absorption by the PLA, with polyurethane presenting the best performance reducing water absorption by 38%. Tensile tests were carried out to determine the ultimate tensile strength, elastic modulus, yield tensile strength, fracture strain and toughness of specimens, before and after the application of protective coatings. The polyurethane protective coating also benefits the tensile properties of PLA parts, increasing the strength and ductility/toughness characteristics of specimens up to 24%.

The Effect of Protective Coatings using L-5A Type toward Corrosion Rate on Mild Steel Grade a Material (Case Study in Indonesia Warship)

The Indonesian Navy requires warship as the main component of defense. It most of the material used are plates. There are several materials or materials that are vulnerable when exposed to corrosive attack on the marine environment. The aim of this paper is to determine the influence of coating, characteristics and compounds corrosion mild steel material A grade toward corrosion rate in seawater environment. Characteristics and corrosion compounds, used salt spray, immersion corrosion method, and X-ray method for analyzing corrosion compounds. The result of salt spray method showed highest corrosion rate (average 7,228 mpy for 20 days). The result of highest without coating showed corrosion rate (average 52,781 mpy for 20 days). The immersion test method with painting has the highest corrosion rate (average 1,892 mpy for 10 days). The highest unpainted corrosion rate (average 4,608 mpy for 20 days) after identified using x-ray obtained analysis and element that cause corrosion. In salt sprays produce corrosion product that is Fe (CO3).

Development of Ion-Plasma Coatings for Protecting Intermetallic Refractory Alloys VKNA-1V and VKNA-25 in the Temperature Range of 1200 – 1250°C

Multilayer heat-resistant ion-plasma coatings for protecting the parts of the hot duct of gas-turbine engines produced from refractory nickel alloys based on VKNA intermetallics from high-temperature oxidation are considered. Coatings of the Ni – Cr – Al (Ta, Re, Hf, Y) + Al – Ni – Y systems are tested for high-temperature strength at 1200 and 1250°C. Metallographic and microscopic x-ray spectrum analyses of the structure and composition of the coatings in the initial condition and after the testing are performed. The effect of protective coatings of the Ni – Cr – Al – Hf + Al – Ni – Y systems on the long-term strength of alloys VKNA-1V and VKNA-25 at 1200°C is studied.

RESULTS OF MECHANICAL RESISTANCE TEST OF LABORATORY SAMPLES COATING APPLIED BY LASER DEPOSITION

The article analyzes the results of tests of mechanical resistance of laboratory specimen coating applied by laser deposition. Based on the analysis a conclusion is drawn about the effect of protective coatings and their application methods on the friction coefficient and relative wear resistance.

Effect of protective coatings on the quality of mango (Mangifera indica L.) in postharvest

El mango ( Mangifera indica L.) es un fruto climaterico de excelsas caracteristicas sensoriales, pero presenta una vida util o de anaquel muy corta, por lo tanto, es necesario explorar alternativas tecnologicas, que permitan prolongar su periodo poscosecha. Dentro de los desarrollos mas estudiados, actualmente, se encuentra la aplicacion de recubrimientos comestibles a frutas de interes comercial, que permitan mejorar sus caracteristicas fisiologicas y sensoriales. En la presente investigacion, se evaluo el efecto de dos recubrimientos comestibles sobre la calidad de frutos de mango. Los frutos fueron recubiertos con soluciones de almidon de yuca ( Manihot esculenta C.) y pectina citrica, en concentraciones de 1,5%. Los mangos, se sumergieron en la solucion durante dos minutos y se almacenaron a 11±1oC y 80±5% de HR. Se evaluo cada tres dias, durante 12 dias, la firmeza, la perdida fisiologica de peso, los parametros triestimulos de color; “CIELab”, el indice de pardeamiento, los solidos solubles totales, la acidez y la calidad sensorial. Se logro concluir que los recubrimientos comestibles, con base en almidon de yuca y pectina permitieron conservar los frutos de mango cv. Criollo durante 12 dias almacenados, en refrigeracion a 11±1oC y 80±5% de HR.

The Effect of Protective Coatings on the Oxidation Behavior of 6061Al/SiC Composite at High Temperatures

This paper analyses the effect of protective coatings on the oxidation behavior of 6061Al/SiC composite material at temperatures ranging from 500 to 800 K. Aluminum and AlCrN coatings are employed as protective coatings in order to improve the oxidation resistance of the composite. SEM, EDAX, XRD and oxidation measurement techniques are used to study the oxidation behavior and to characterize the composite specimens. Oxidation of the composite material without protective coatings is seen to be very rapid during the initial stages of exposure to the high temperatures but subsequently slowed down due to the formation of a protective surface layer of oxide. The oxidation was especially severe above 600 K. The interface between the matrix and reinforcement particles and the grain boundary regions of intermetallic precipitates in the matrix enhance this oxidation process since they provided sites for oxidation initiation. Aluminum coating on the composite obtained by DC magnetron sputtering technique and AlCrN coating obtained by low voltage electron beam evaporation technique reduce the oxidation rate effectively since the interface regions between the matrix and reinforcement, grain boundary regions of the matrix are unexposed to the atmosphere. Aluminum coating provides better oxidation resistance for 6061 Al/SiC composites.

Effect of protective coatings on mechanical properties of ZhS32-VI heat-resistant alloy

We discuss the effect of diffusion heat-resistant and condensation gradient thermal barrier coatings used for protection of gas turbine disk operating blades on mechanical characteristics (long- and short-term durability and plasticity at temperature of 1000°C) of specimens from ZhS32-VI heat-resistant alloy. We study the effect of isothermal annealing in air at temperature 1100°C during 240 h on mechanical characteristics of uncoated and coated specimens. We note the expediency of application of gradient thermal barrier coating consisting from external heat-insulating ceramic layer and thermostable heat-resistant metal layer, which provide temperature reduction of metal walls of cooled blades made from ZhS32-VI heat-resistant alloy with the purpose of achieving the required residual life.

Semi-analytical study of wave propagation in wire waveguides.

Guided ultrasonic waves in wire waveguides are useful for various applications including position monitoring and in-situ measurements of specimens in harsh environments. In corrosive environments, it has been observed that the velocity of the guided waves changes due to the growth of an oxide layer on the waveguide. Previous work by Grossman [IEEE Trans. Sonics Ultrason. 31, 25–31 (1984)] analyzed this phenomenon by calculating the change in rod velocity due to oxide thickness. In this paper, the semi-analytical finite element (SAFE) method was used to determine how the velocity changes with respect to oxide thickness and frequency. In addition, the effects of protective coatings on the waveguide have been considered. Results demonstrate that the SAFE method is effective for determining the dispersion characteristics of a waveguide comprised of two distinct materials.

Effect of protective coatings on the properties of welded joints

Effect of protective coatings on the properties of welded joints

高温強度 Ｎｉ基超合金ＩＮ７３８ＬＣ耐食コーティング材の疲労強度推定法の検討

The effect of protective coatings on the high-cycle fatigue strength of Ni-base superalloy, IN738LC, was first modeled, summarizing the previous studies which covered the fatigue failure of the IN738LC specimens with three kinds of protective coatings: the CoCrAlY alloy overlay coated IN738LC, the CoNiCrAlY alloy overlay coated IN738LC, and the combined coatings in which the aluminide coating was conducted with different thickness on the CoNiCrAlY overlay coated IN738LC. The effect was found to be condensed into the following roles, depending on the mechanical properties of the coating material and substrate: the role as a fatigue crack initiator, the role to make a geometrical change of fatigue crack, and the role to induce a stress concentration. A new semi-empirical method to predict the fatigue endurance of the coated material was proposed, by applying the concept of latent, or fictitious crack, which has been originally introduced by Haddad et al. to explain the dependence of crack length on threshold of fatigue cracks in monolithic materials. In the proposed method the coating and the incidental diffusion zone were treated as a part of latent crack interacting with the substrate, depending on the mechanical properties of coating material. It was shown that the proposed method gave a good estimation corresponding well with the experimental results.