Enamel industrial porcelain (also known as glass layer , glass-coated steel , or glass that fused with steel ) is use of enamel porcelain (also known as vitreous enamel) for industrial applications, not artistic. Porcelain porcelain, ceramic or glass coating applied to metal substrates, is used to protect the surface from chemical attack and physical damage, modify structural characteristics of substrate, and improve product appearance.
Enamel has been used for art and decoration since the days of Ancient Egypt, and for industry since the Industrial Revolution. It is most commonly used in the production of cookware, home appliances, bathroom fixtures, water heaters, and scientific laboratory equipment.
Video Industrial porcelain enamel
Characteristics
The most important characteristic of porcelain enamel, from an industrial perspective, is its resistance to corrosion. Lightweight steel is used in almost every industry and a large number of products; enamel porcelain is a very economical way to protect this, and other vulnerable chemicals, from corrosion. It can also produce very smooth and shiny finishes in a variety of colors; these colors will not fade on UV exposure, as does the paint. Being ceramic fired, porcelain enamel is also very heat resistant; this allows for use in high temperature applications where an organic or galvanizing anti-corrosion coating may be impractical or even harmful (see Metallic Fever ).
Porcelain enamel also sees less work than some other properties; an example is its abrasion resistance, where it can perform better than many metals; its resistance to organic solvents, where it is fully resistant; its resistance to thermal shock, where it can withstand rapid cooling of 500Ã, Â ° C and higher temperatures; and its longevity.
Maps Industrial porcelain enamel
Apps
Porcelain enamel is most commonly used in the manufacture of products that would be expected to come under regular chemical or high heat attacks like cookware, burners, and laboratory equipment. It is used in the production of many household items and appliances, especially those used in kitchens or bathrooms: pots, pans, stoves, appliances, sinks, toilets, bathtubs, even walls, counters, and other surfaces.
Porcelain china is also used architecturally as a coating for wall panels. It can be used externally to provide the desired weather resistance and appearance, or internally to provide wear resistance; for example, on the side panels of the escalator and the tunnel wall. In recent years, agricultural silos have also been built with steel plates in porcelain to protect the interior from corrosion and the exterior of weathering; this may indicate the future trend of coating all lightweight outdoor steel products in weatherproof porcelain enamels.
The Enamelling Process
The application of industrial porcelain enamel can be a complicated process involving many different and highly technical steps. All coating processes involve mixtures and preparations of frit , unused enamel mixtures; substrate preparation; application and burning; and then complete the process. Most modern applications also involve two layers of enamel: a soil layer to bind to the substrate and cover layer to provide the desired external properties.
Since frits often have to be mixed at higher temperatures than required combustion, most modern industrial enamels do not mix their frit fully; frit is most often purchased from frit manufacturers specialized in standard compositions and then special ingredients added before application and burning.
Frit
For soil layers, the frit composition for each application is determined primarily by the metal used as the substrate: different steel varieties, and different metals such as aluminum and copper, require different frit compositions to bind them. For the cover layer, the frit is arranged to bind the soil layer and produce the desired external properties. Frit is usually prepared by mixing the ingredients and then stirring the mixture into a powder. Materials, most commonly metal oxides and minerals such as quartz (or silica sand), soda ash, borax, and cobalt oxide, are obtained in particle form; the exact chemical composition and the amount of each ingredient must be carefully measured and regulated. Once ready, the powdered frit is then collapsed and stirred to promote even distribution of the ingredients; most frit is melted at a temperature between 1150 and 1300 ° C . After the smelting, the frit is again ground into a powder, most often with a ball mill.
For wet applications of email, a suspended slurry of slurry in water must be created. To remain in suspension, the frit should be ground into a very fine particle size or mixed with a suspension agent such as clay or electrolyte.
Substrate
The metal to be used as a substrate is primarily determined by the application in which the product will be placed, regardless of enamel consideration. Most commonly used are steels of various compositions, but also used are aluminum and copper.
Before enamel application, the substrate surface should be prepared with a number of processes. The most important process is the cleaning of the substrate surface; all remaining chemicals, rust, oil, and other contaminants must be completely removed. To facilitate this, the process often done on the substrate is degreasing, preservation (which can also etch the surface and provide anchor point for email), alkaline neutralization, and rinsing.
Apps
Enamel can be applied to the substrate through many different methods. This method is most often depicted in the application of wet or dry , determined by whether the enamel is applied as a dry powder or a slurry suspension.
Application is dry
The simplest dry application method, especially for the iron substrate, is to heat the substrate and roll it in a powdered frit. The frit particles melt when in contact with the heat substrate and adhere to its surface. This method requires the skill and concentration of high level operators to achieve a uniform layer, and due to its non-constant nature is not often used in industrial applications.
The most common dry application method used in industry today is electrostatic deposition. Prior to application, dry frit should be encapsulated in organic silane; this allows the frit to hold the electrical charge during the application. The electrostatic gun fires dry frit powder onto an electrically grounded metal substrate; electric power binds the charged powder to the substrate and follows it.
Wet app
The simplest method of wet application is to dip the substrate into a slurry bath; complete immersion coat of all available substrate surfaces. Dipping is not often used in industry, however, since many initial trial trials are required before the thickness of the coat can be predicted reliably enough for the desired application.
A suitable immersion form for modern industrial applications is flow coating. Instead of dipping the product into a slurry bin, the slurry flows over the surface of the product to be coated. This method allows the use of slurry and a much more economical time; he was able to allow production to run very quickly.
Wet enamel can also be sprayed onto the product using a special spray gun. The liquid slurry is inserted into the spray gun nozzle, and the compressed air sprays the slurry and removes it from the pistol nozzle in controlled jet.
Enable
The activation, in which the coated substrate is passed through the furnace to experience a period of stable stable high temperature, converting the particles attached to the frit into a continuous glass layer. The effectiveness of the process depends on the time, temperature, and quality or thickness of the coating on the substrate. Most frit for industrial applications are fired as low as 20 minutes, but frit for very heavy industrial applications can be done twice this time. Porcelain enamel coating on the aluminum substrate can be fired at temperatures as low as 530 ° C, but most of the steel substrate requires temperatures greater than 800 ° C.
History
Porcelain porcelain has been applied to jewelry metal such as gold, silver, and copper since ancient for decorative purposes. It was not until the Industrial Revolution that the first iron metal became the subject of the porcelain enamel process; this first attempt was filled with limited success. Reliable and successful techniques were not developed until the mid-19th century, with the development of the iron cookware enamel method in Germany. It was not long before this enamel method became obsolete with the development of new iron substrate, and much of modern research into porcelain enamel was concerned with creating an acceptable bond between the enamel and the new metal substrate.
The production of enameled porcelain products on the first industrial scale began in Germany in 1840. The method used is very primitive compared to modern methods: the product is heated to a very high temperature and sprinkled with enamel, then immediately fired. This often results in poor adhesion or an untidy coat; two layers are always required to achieve a continuous surface, corrosion-resistant. It can only be applied to wrought iron and wrought iron, and is only used for relatively simple products such as pots and pans.
The ability to apply porcelain enamel to sheet steel was not developed until 1900, with the discovery that making small changes to the enamel composition, such as including cobalt oxide as a small component, can drastically increase the adhesion capability to carbon steel. Along with this development is the first use of wet-slurry enamel application; this allows porcelain enamel to be applied to a much more complicated shape by dipping the shape into an enamel enamel slurry.
Until the 1930s, all enamel applications required two layers of enamel: the bottom layer to adhere to a substrate that was always blue (partly due to the presence of cobalt oxide), and the desired top layer of color (most often white). It was not until 1930 that the use of zero carbon steel (steel with carbon content less than 0.005%) as the substrate was associated with allowing a lighter colored enamel to adhere directly to the substrate.
References
Bibliografi
- Maskall, K.A.; Putih, D. (1986). Enamings Vitreous: Panduan untuk Praktek Enameling Modern . The Pergamon Materials Engineering Practice Series (edisi 1). Pergamon Press, atas nama The Institute of Ceramics. ISBN: 0-08-0334288. Â
- Clarke, Geoffrey; Feher, Fracis & amp; Ida (1967). Teknik Enamelling . New York: Reinhold Publishing Corporation.
Source of the article : Wikipedia
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