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Poles, Cross Arms, Pins, Racks, and Insulators
Published in Anthony J. Pansini, Electrical Distribution Engineering, 2020
Porcelain is made from white clay to which powdered feldspar and silica are added. The material has greater (compared to glass) ability to resist sudden changes in temperature, and an external glaze protects it from shock. Depending on how insulators are manufactured, the tensile strength of the porcelain may vary from less than 2000 lb/in2 to as much as 9000 lb/in2, and the corresponding minimum compressive strengths, from 15,000 to 60,000 lb/in2; its coefficient of expansion may be as low as 16.6 × 10-6 per degree Fahrenheit, or 30 × 10-6 per degree centigrade. The dielectric strength generally exceeds 16 kV/mm (16,000 kV/m), or some 400 kV/in.
Whiteware and Glazes
Published in Debasish Sarkar, Ceramic Processing, 2019
A fritted glaze that has matured at 1100°C–1150°C is generally used. The major difference between porcelain and bone china ware is that porcelain ware is made when the body and glaze have matured during the same firing, whereas bone china bodies are made first by vitrification of the body followed by maturing the applied glaze at a slightly lower temperature. Hotel chinaware, primarily used in hotels and restaurants, possess properties akin to porcelain and bone chinaware. Hotel chinaware is generally fired to complete vitrification and a glaze is applied to the ware, which is matured at a somewhat lower temperature. The typical composition of a hotel china body is kaolin ~30%–35%, ball clay ~8%–12%, flint ~35%–45%, potash feldspar ~12%–15%, soda feldspar ~2%–5%, and dolomite ~1%–1.5%. Due to presence of high alumina in the body composition a large amount of mullite formation is observed in the fired body, which provides high strength. The vitrified body also contains siliceous glass generally derived from undissolved silica particles of flint. The fluxes melt early and form liquid phases that help to dissolve the alumina and silica from the clay composition and allow the crystallization of mullite.
Densification
Published in David W. Richerson, William E. Lee, Modern Ceramic Engineering, 2018
David W. Richerson, William E. Lee
Porcelain compositions (such as compositions in the K2O–Al2O3–SiO2 phase diagram) are important traditional ceramics and are densified by VCS as described in Section 12.1.3. Porcelain ceramic applications include china, sinks, porcelain enamels, insulators, and many ceramics used in electronics. A common porcelain body is fabricated from about 50% kaolin clay (~45% Al2O3, 55% SiO2), 25% potash feldspar, and 25% SiO2. Enough liquid is present in this system above about 1200°C (2190°F) to achieve VCS or vitrification which involves much larger liquid contents than liquid-phase sintering (>20% liquid). As a review, look up the K2O–Al2O3–SiO2 phase equilibrium diagram and draw isothermal sections at 1200°C, 1300°C, and 1400°C (2190°F, 2370°F, and 2550°F). Note the extent of the liquid plus solid regions and how they increase as the temperature increases. Increased amounts of liquid phase increase the rate of sintering.
Effect of green synthesized silver nanoparticles on optical behavior of feldspathic porcelain
Published in Particulate Science and Technology, 2022
Farnaz Firoz, Fariborz Vafaee, Abas Farmany, Maryam Farhadian, Soodabe Ebrahimi
Although porcelain is mainly used in dentistry to achieve cosmetic restorations in the oral cavity. Should be strong enough to withstand the chewing forces and durability in the oral environment (Anusavice, Shen, and Lee 1992). Porcelain is susceptible to the fracture under the high occlusal forces such as bruxism due to its fragility. Therefore repairs are sometimes necessary in porcelain fractures or chipping cases (Reitemeier et al. 2006).
Properties of porcelain influenced concrete
Published in European Journal of Environmental and Civil Engineering, 2022
Khaled M. Amtered El-Abidi, Mustafa Juma A. Mijarsh, Noor Faisal Abas
In this research, porcelain polishing residue (PPR) was used, it is the main residue in the sludge with above 1% loss rate. Porcelain is a material that is produced through the heating of ceramic clays materials in a kiln at a temperature between 1200 °C and 1400 °C. The chemical composition of the porcelain, PPR, is shown in Table 1.