scholarly journals Obtaining Luminous Phosphate Coatings on Steel by Cold Method

2022 ◽  
Author(s):  
V.S. Konovalova

Abstract. The possibility of obtaining luminous phosphate coatings on steel by cold method has been studied. Modified cold phosphating solutions containing organic additives (glycerin, trilon B, OS-20 emulsifier) were selected as the basis to maintain the pH, stabilize the solution and improve the quality and structure of the deposited coatings. To obtain the glow effect, a green phosphor based on Zn2SiO4 containing manganese as a sensitizer was added to the phosphating solution. During deposition, phosphate coatings are obtained that glow with spots, but constant mixing of the solution during deposition contributes to the uniform distribution of phosphor in the phosphate film. Luminous phosphate coatings have good protective properties, they can be used as an independent protection of steel surfaces from corrosion.

2012 ◽  
Vol 90 (6) ◽  
pp. 330-333 ◽  
Author(s):  
L Fachikov ◽  
Y Tumbaleva ◽  
D Ivanova ◽  
B Tzaneva

2007 ◽  
Vol 4 (11) ◽  
pp. 581-595 ◽  
Author(s):  
J. F. Andrew ◽  
S. G. Clarke ◽  
E. E. Longhurst

Author(s):  
Е.Г. Раковская ◽  
О.А. Кудряшова

Исследование посвящено изучению возможности применения преобразователя ржавчины П-2 при подготовке поверхности стали к окрашиванию с целью замены экологически вредных механических способов очистки и улучшения его защитных свойств путем введения органических ингибиторов. При механической обработке металлов в больших количествах выделяются мелкодисперсные частички лака, мелкодисперсная металлическая пыль, оксиды металлов (Fe, Al), которые негативно действуют на человека. Для замены вредных для окружающей среды механических способов очистки металлической поверхности предлагается подготовка без удаления продуктов коррозии, которая заключается в нанесении на ржавую поверхность модификаторов или грунтов модификаторов ржавчины. Суть действия модификаторов ржавчины состоит в их способности стабилизировать состояние ржавчины и обезвреживать агрессивные примеси. Ингибиторы коррозии с каждым годом приобретают все большее значение в противокоррозионной защите металлических изделий. Успехи в области разработки научных основ действия ингибиторов и создания новых ингибиторов различного назначения позволили предложить метод противокоррозионной защиты, который основан на введении ингибиторов в лакокрасочные покрытия. Преобразователи ржавчины преобразуют продукты коррозии в нерастворимые соединения, образующие защитные слои, на которые затем наносятся лакокрасочные материалы. Для исследования кинетики электрохимических реакций использовался метод снятия поляризационных кривых с помощью потенциостата П-5828 М. Испытания проводились на стали 3 и стали У8А. Кинетика процессов, протекающих при пассивации, изучалась методом снятия анодных потенциостатических кривых, также определялись сопротивление защитных пленок, выход по току и скорость коррозии. Исследование влияния N- и S-содержащих органических соединений на параметры пассивации стальных образцов в среде преобразователя ржавчины П-2 показало, что данные добавки способствуют переходу стали в пассивное состояние, уменьшают ток пассивации, способствуют увеличению сопротивления пассивных пленок. Следствием такого влияния органических добавок на параметры пассивации является уменьшение выхода металла по току, а следовательно, и уменьшение скорости коррозии. Результаты исследования могут быть использованы при подборе ингибиторов, вводимых в преобразователь ржавчины П-2, для более эффективной защиты металла от коррозии и безопасности здоровья человека. The real work is devoted to studying of a possibility of use of the P-2 rust solvent for preparation of a surface of steel for coloring for the purpose of replacement of ecologically harmful mechanical ways of cleaning and improvement of its protective properties by introduction of organic inhibitors. When machining metals in large numbers fine parts of a varnish, fine metal dust, oxides of metals (Fe, Al) which negatively affect the person are allocated. For replacement of mechanical ways of cleaning of a metal surface, harmful to the environment, preparation without removal of products of corrosion which consists in drawing on the rusty surface of modifiers or soil of modifiers of a rust is offered. The essence of operation of modifiers of a rust consists in ability to stabilize their condition of a rust and to neutralize aggressive impurity. Corrosion inhibitors gain the increasing value in anticorrosive protection of metal products every year. Achievements in the field of development of scientific bases of effect of inhibitors and creation of new inhibitors of different function have allowed to offer a method of anticorrosive protection which is based on introduction of inhibitors to paint and varnish coverings. Rust solvents will transform corrosion products to the insoluble connections forming protective layers on which then paints and varnishes are applied. For a research of kinetics of electrochemical reactions the method of removal of polarizing curves by means of a potentsiostat of P-5828 of M was used. Tests were carried out on steel 3 and U8A steel. The kinetics of the processes proceeding at passivation was studied by method of removal the anodic potentiostatic curves, resistance of protective films, an exit was also determined by current and corrosion speed. The research of influence of N-and S-of the containing organic compounds on parameters of passivation of steel samples in the environment of the P-2 rust solvent has shown that these additives promote transition of steel to a passive state, reduce passivation current, promote increase in resistance of passive films. Reduction of an exit of metal on current and consequently, and reduction of speed of corrosion is a consequence of such influence of organic additives on parameters of passivation. Results of work can be used at selection of the inhibitors entered into the P-2 rust solvent for more effective protection of metal against corrosion and safety of health of the person.


Coatings ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 70
Author(s):  
Evgeniy Rumyantsev ◽  
Varvara Rumyantseva ◽  
Viktoriya Konovalova

The article presents a method for obtaining white phosphate coatings on steel by cold method. The deposition of protective phosphate coatings was carried out from solutions based on the preparation “Majef”, consisting of manganese and iron phosphates. To obtain phosphate films of white color, it is proposed to introduce zinc and calcium nitrates into phosphating solutions at the rate of 25–30 g/L. The surface of phosphate coatings was studied using the SolverP47-PRO atomic force microscope images, and the average grain size was determined. The structural and phase composition of phosphate coatings was been studied using X-ray diffraction analysis. The protective properties of phosphate coatings were estimated by corrosion rate indicators calculated from corrosion diagrams. Fine-crystalline uniform coatings were obtained from modified phosphating solutions at room temperature on steel. The white color of phosphate coatings is due to the increased content of phosphophyllite, hopeite, and parascholzite in their structural and phase composition. By applying protective phosphate coatings of white color on a steel product, corrosion can be slowed down by 4–4.5 times. However, white phosphate coatings are inferior in protective properties to unpainted coatings. The index of change in the mass of samples with white phosphate coatings because of corrosion is 0.371–0.41 g/(m2·h), and with unpainted coatings is 0.128 g/(m2·h).


2021 ◽  
Vol 2131 (4) ◽  
pp. 042027
Author(s):  
V Rumyantseva ◽  
V Konovalova ◽  
B Narmaniya

Abstract The deposition of phosphate coatings occurs on the surface of the product when it is immersed in a solution containing phosphoric acid. The formation of a film on the metal surface occurs during the deposition of insoluble two- and three-substituted phosphates of iron, manganese, and zinc from a solution. To speed up the process and conduct phosphating at low temperatures, nitrates, nitrites, and fluorides of active metals are introduced into the solution. Organic compounds, such as glucose, glycerin, Trilon A, and Trilon B, are buffer additives to maintain the pH of phosphating solutions in the range of 2.6-3.2. It was found that 10-15 minutes at a process temperature of 20-25 °C are sufficient for the formation of a protective phosphate coating from solutions containing modifiers. The content of zinc phosphates in the modified phosphate coatings is increased. Additives in cold phosphating solutions have a positive effect on the quality and protective properties of the resulting phosphate films. Modified phosphate coatings obtained by the cold method have a fine-crystalline structure, a smooth surface and low porosity.


2020 ◽  
Vol 329 ◽  
pp. 02001
Author(s):  
Viktoriya Konovalova

The influence of phosphate coatings on the corrosion behavior of steel reinforcement in a chloride-containing environment was studied to determine the need for additional protection against corrosion. The main indicators of the corrosion rate of steel reinforcement with phosphate coatings in chloride-containing solutions were determined, confirming the high protective properties of these coatings. It was found that the corrosion rate of steel reinforcement protected by phosphate coatings is reduced by 3 times. The processes of electrochemical corrosion of steel reinforcement of strength class A500S from steel grade St3ps in concrete under the influence of aggressive environments containing chloride ions (2 % MgCl2 solution and HCl solution with pH = 5) were studied. The kinetics of the corrosion process of steel reinforcement with and without protective phosphate coatings in solutions of various compositions has been studied. The change in mass of steel reinforcement protected by phosphate coatings is 3-4 times less than that of samples without coating. The surface potential of steel reinforcement with phosphate films changes significantly more slowly than that of unprotected samples.


2021 ◽  
Vol 346 ◽  
pp. 01034
Author(s):  
Viktoriya Konovalova

This work is devoted to the study of the physical-mechanical and protective properties of modified phosphate coatings obtained on steel by cold method. Modifiers introduced into phosphating solutions are buffer additives, stabilize the phosphating process, allow the deposition of coatings at low temperatures, increase the number of active centers on the metal surface, resulting in fine-crystalline uniform coatings of small thickness. It was found that the corrosion rate of modified phosphate films is 2 times less than that of coatings obtained by the traditional method. When the temperature rises above 100 °C, the corrosion resistance of phosphate coatings decreases, and the satisfactory protective properties of the modified films are preserved when heated to 200 °C. Modified phosphate coatings have a high adhesion strength to the metal due to their small thickness. However, thin phosphate coatings have low wear resistance and medium electrical insulation properties.


2019 ◽  
Vol 298 ◽  
pp. 00126 ◽  
Author(s):  
Sergey Fedosov ◽  
Varvara Roumyantseva ◽  
Viktoriya Konovalova

Phosphate coatings are successfully applied as a method of protecting steel products and structures from corrosion. Phosphate coatings mechanically prevent the entry of aggressive particles, such as chloride ions, to the surface of steel reinforcement. The parameters of corrosion rate of reinforcing steel in aggressive environment are determined by graphical method. The analysis of corrosion diagrams allows us to judge the effect of protective phosphate coatings on the kinetics of the corrosion process of steel reinforcement in environments of varying degrees of aggressiveness. The tests of the protective properties of phosphate coatings by contact corrosion method show that films with a finer crystal structure, as in modified phosphate coatings, are more resistant to anodic dissolution of steel. In parallel to determination of iron ions content in solutions the potential of steel reinforcement samples was measured. In samples protected by phosphate films, the potential change is not as sharp as in samples without coating, and the “dilution” of steel is slower. The study of anodic behavior of steel reinforcement of reinforced concrete, experimental study of the mass transfer mechanism of electrolyte supply to the surface of reinforced steel allow to develop practical recommendations to improve corrosion resistance and ensure the durability of reinforced concrete building materials.


Author(s):  
Е.Г. Раковская ◽  
О.А. Кудряшова

Работа посвящена исследованию защитных свойств преобразователя ржав- чины, наносимого на прокорродировавшую поверхность при введении в него ор- ганических добавок для создания покрытий с улучшенными защитными свойствами. Опыт эксплуатации деталей лесотранспортных машин, контактирующих с агрессивными средами, показывает, что если не защищать наиболее ответствен- ные детали конструкций специальными средствами, либо не применять материалы специального химического состава, то в результате возникновения процессов коррозии произойдёт коррозионно-механическое разрушение конструкции. Наиболее распространенным способом защиты металлов от коррозии является нане- сение лакокрасочных покрытий. Однако долговечность и эффективность такой защиты в значительной степени определяется качеством подготовки поверхно- сти перед окрашиванием. При нанесении преобразователя П-2 на ржавую поверхность ортофосфорная кислота, входящая в его состав, связывает ионы железа в труднорастворимые фосфаты, блокирующие поверхность металла. Но при обработке кислыми модификаторами поверхности, неравномерно покрытой про- дуктами коррозии, остаточная кислотность на участках. менее загрязненных продуктами коррозии, будет выше, чем на участках. сильно проржавевших, т. е. будет наблюдаться перетравливание поверхности. Поэтому введенные добавки выполняют роль ингибиторов кислотной коррозии. Электрохимические исследо- вания показали, что наибольшее положительное значение потенциалов в случае покрытий с добавками n-аминобензолсульфамид, [5-нитрофурфурола, семикар- базон], [2-(n-аминобензолсульфамидо)-4,6-диметилпиридин]. Исследуемые добавки ингибируют как анодный, так и катодный процессы. Ингибиторный эф- фект возрастает с повышением потенциала поляризации. Показано, что добавки n-аминобензолсульфамид, [5-нитрофурфурола, семикарбазон], [2-(n- аминобензолсульфамидо)-4,6-диметилпиридин] являются наиболее эффективными ингибиторами коррозии, при их введении в преобразователь ржавчины П- 2, что позволяет рекомендовать их к использованию для защиты от коррозии техники в лесном хозяйстве. The work is devoted to the study of the protective properties of the rust converter applied to the corroded surface when organic additives are added to it to create coatings with improved protective properties. Experience in the operation of parts of forest transport vehicles in contact with corrosive environments shows that if the most critical parts of structures are not protected by special means or the materials of special chemical composition are not applied, corrosion corrosion will occur as a result of corrosion processes. The most common way to protect metals from corrosion is the application of paint and varnish coatings. However, the durability and effectiveness of such protection is largely determined by the quality of preparation of the surface before painting. When the P-2 converter is applied to a rusty surface, orthophosphoric acid, included in its composition, binds iron ions to hardly soluble phosphates blocking the surface of the metal. But when treated with acidic surface modifiers unevenly coated with corrosion products, residual acidity in areas less contaminated with corrosion products will be higher than in areas heavily rusted, i. E. Surface re-etching will be observed. Therefore, the additives introduced serve as inhibitors of acid corrosion. Electrochemical studies showed that the greatest positive potentials in the case of coatings with additives of p-aminobenzenesulfonamide, [5- nitrofurfural, semicarbazone], [2- (p-aminobenzenesulfamido) -4,6-dimethylpyridine]. The test additives inhibit both anodic and cathodic processes. The inhibitory effect increases with increasing polarization potential. It has been shown that the additions of n-aminobenzenesulfamide, [5-nitrofurfurol, semicarbazone], [2- (p-aminobenzenesulfamido)-4,6-dimethylpyridine] are the most effective corrosion inhibitors when they are introduced into the P-2 rust converter, Their use for protection from corrosion technology in forestry.


Biofouling ◽  
2003 ◽  
Vol 19 (3) ◽  
pp. 159-168 ◽  
Author(s):  
Nadia Oulahal- Lagsir ◽  
Adele Martial- Gros ◽  
Marc Bonneauc ◽  
Loic Bluma

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