Porcelain enamel is a fusion bonded glass coating that resists chemical and abrasive attack, provides thermal and electrical insulation, and improves aesthetic qualities. It is used on cast iron as well as steel and aluminum alloys. This article provides a review of the porcelain enameling process, the composition of frits, and the preparation of coating substrates. It also provides information on chemical, mechanical, and electrical properties and sheds light on process consistency and quality control.

Porcelain enamels are glass coatings applied primarily to products or parts made of sheet steel, cast iron, or aluminum to improve appearance and to protect the metal surface. This article provides information on the types and properties of the porcelain enamels and frits for porcelain enameling. It describes the corrosion resistance of the porcelain enamels in a variety of environments. Evaluation of properties of the porcelain-enameled products to control specifications and quality of porcelain-enamel coatings is also reviewed. The article contains a table that lists the specific test methods for evaluating various properties of porcelain enamels.

Porcelain enamels are glass coatings applied primarily to products or parts made of sheet steel, cast iron, and aluminum to improve appearance and to protect the metal surface. This article describes the types of porcelain enamels, and details enamel frits for these materials. It provides a list of steels suitable for porcelain enameling and discusses the most important factors considered in the selection of steel for porcelain enameling. The article briefly presents the preparation methods of these materials for porcelain enameling and covers the methods, and furnaces of porcelain enameling. It examines the role of coating thickness, firing time and temperature, metal substrate, and color on the performance of enameled surfaces. The article concludes with a discussion on the properties of enameled surfaces, factors considered in process control, and test procedures for evaluating the quality of enameled surfaces.

Ceramic coatings are applied to metals to protect them against oxidation and corrosion at room temperature and at elevated temperatures. This article provides a detailed account of the factors to be considered when selecting a ceramic coating and describes the characteristics of various coating materials, namely, silicate glasses, oxides, carbides, silicides, and cermets. It reviews ceramic coating methods: brushing, spraying, dipping, flow coating, combustion flame spraying, plasma-arc flame spraying, detonation gun spraying, pack cementation, fluidized-bed deposition, vapor streaming, troweling, and electrophoresis. The article also includes information on the evaluation of the quality of ceramic coatings.

There are various coating techniques in practice to prevent the deterioration of steels. This article focuses on dip, barrier, and chemical conversion coatings and describes hot-dip processes for coating carbon steels with zinc, aluminum, lead-tin, and other alloys. It describes continuous electrodeposition for steel strip and babbitting and discusses phosphate and chromate conversion coatings as well. It also addresses painting, discussing types and selection, surface preparation, and application methods. In addition, the article describes rust-preventive compounds and their application. It also provides information on weld-overlay and thermal spray coating, porcelain enameling, and the preparation of enamel frits for steels. The article closes by describing methods and materials for ceramic coating.

Traditional ceramics, one of two general classes, are commonly used in high-volume manufacturing to make building materials, household products, and various industrial goods. Although there is a tendency to equate traditional ceramics with low technology, sophisticated processes and advanced manufacturing techniques are often used where these materials are employed. This article examines several traditional ceramics, including structural clay, whiteware, glazes, enamels, portland cements, and concrete. It also provides a detailed account of fabrication methods, properties, and applications. As an example, common applications for structural clay include facing materials, load-bearing units, pavers, and ceramic tiles.

Several qualitative, semiquantitative, and quantitative tests are available to estimate and control metal cleanliness, particularly inclusion concentration of aluminum alloys. This article provides a description of a few of the metal cleanliness assessment techniques, such as chemical analysis, pressure filter tests, electric resistivity tests, reduced-pressure test, and ultrasonic technique. Detection methods based on the certain principles and the types of impurities in chemical analysis are discussed.

This article provides a brief discussion on the common types of overlayers that can be used on a metal surface to protect it from corrosion. These overlayers include phosphate, chromate, and chromate-free conversion coatings; hot dip galvanizing; cementitious linings; glass and porcelain enamels; electroplating; thermal spray coatings; and rubber linings.

This article focuses on the ceramic coatings for ceramic and glass substrates. It describes the role of oxides in glazes and discusses the optical and appearance properties of various types of glazes, such as leadless glazes, lead-containing glazes, opaque glazes, and satin and matte glazes. The article provides information on the classification of pigments and the applications of ceramic coatings for decorations on ceramic and glass surfaces.

Aluminum or aluminum alloy products have various types of finishes applied to their surfaces to enhance appearance or improve functional properties. This article discusses the procedures, considerations, and applications of various methods employed in the cleaning, finishing, and coating of aluminum. These include abrasive blast cleaning, barrel finishing, polishing, buffing, satin finishing, chemical cleaning, chemical brightening, electrolytic brightening, chemical etching, alkaline etching, acid etching, chemical conversion coating, electroplating, immersion plating, electroless plating, porcelain enameling, and shot peening.

Ceramic and glass manufacturers take environmental regulations into consideration during all stages of the product cycle, from research and development to purchasing, processing, end use, and disposal. Ceramic and glass products are finding application in the construction industry and as raw materials for other processes. This article describes the recycling of in-process scrap and industrial wastes (fly ash, red mud, metallurgical waste, and other waste products), and applications of these recycled products. It focuses on environmental regulations such as Resource Conservation and Recovery Act and Clean Air Act. The Clean Air Act requires all states to meet minimum emissions standards for nitrogen-oxygen compounds, volatile organic compounds, and carbon monoxide.

This article provides a brief review of the classification and characteristics of cast irons. It describes the processes used to clean iron castings, including mechanical cleaning and finishing and nonmechanical cleaning. The article discusses surface treatments used to extend casting life when resistance to corrosion, wear, and erosion is required. The common methods include electroplating, electroless plating, hardfacing, weld cladding, surface hardening, porcelain enameling, and organic coatings.

This article reviews the applications of traditional glasses in architecture, transportation, construction, houseware, containers, and fibers. It also describes uses of specialty glasses for aerospace and military applications, biomedical and dental applications, chemical-resistant applications, lighting, information display, electronic processing and electronic devices, optical and ophthalmic products, and communications equipment.

Coating of cast irons is done to improve appearance and resistance to degradation due to corrosion, erosion, and wear. This article describes inorganic coating methods commonly applied to cast irons. The coating methods include plating, hot dip coating, conversion coating, diffusion coating, cladding, porcelain enameling, and thermal spray. Organic coatings have a wide variety of properties, but their primary use is for corrosion resistance combined with a pleasing colored appearance. The article discusses the various types of organic coatings applied to cast irons. Practically any degree of smoothness or roughness and requirement for color and gloss can be filled by organic coatings. The article describes abrasive blast cleaning, abrasive waterjet cleaning and finishing, vibratory finishing, barrel finishing, and shot peening for processing iron castings.

Zinc and zinc alloys require surface engineering prior to coating or use to improve adhesion and corrosion resistance. Die-cast zinc parts, in addition, must be trimmed and finished to remove flash and parting lines. This article covers zinc cleaning procedures as well as coating and finishing processes. It explains how to remove parting lines and presents several mechanical finishing methods, including surface polishing, brushing, controlled shot peening, and buffing. It also provides information on solvent cleaning, emulsion cleaning, aqueous detergent or alkaline cleaning), electrocleaning, acid dipping, and zinc conversion coating treatments.

This article addresses surface cleaning, finishing, and coating operations that have proven to be effective for molybdenum, tungsten, tantalum, and niobium. It describes standard procedures for abrasive blasting, molten caustic processing, acid cleaning, pickling, and solvent and electrolytic cleaning as well as mechanical grinding and finishing. The article also provides information on common plating and coating methods, including electroplating, anodizing, and oxidation-resistant coatings.

This article focuses on the process methods and matrix chemistries of ceramic-matrix composites. These methods include pressure-assisted densification, chemical vapor infiltration, melt infiltration, polymer infiltration and pyrolysis, and sol-gel processing. The article discusses the use of a ceramic, preceramic, or metal phase as a fluid or vapor phase reactant to form the matrix. Emphasis is placed on microstructural features that influence ultimate composite properties.

Ceramic materials serve important insulative, capacitive, conductive, resistive, sensor, electrooptic, and magnetic functions in a wide variety of electrical and electronic circuitry. This article focuses on various applications of advanced ceramics in both electric power and electronics industry, namely, dielectric, piezoelectric, ferroelectric, sensing, magnetic and superconducting devices.

The large majority of the commercially important glasses are processed from a carefully calculated batch of raw materials that is then melted in special furnaces. Providing an introduction to melting practices of glass production, this article focuses on various finishing methods of glass products, including forming, grinding and polishing, and explores the advantages, disadvantages and steps involved in sol-gel process. It also discusses the types, processes and properties of annealed, laminated, and tempered glass, and presents the steps involved in glass decoration. The article gives a detailed account of production, properties and application of fiberglass, optical fibers, glass spheres and ceramic glasses, and describes the forms, classification, compositions and properties of glass/metal and glass-ceramic/metal seals.

This article describes the principles and classifications of induction furnaces. The classifications of induction furnaces are coreless and channel. The electromagnetic stirring action in these furnaces is reviewed. The article provides information on the various power supplies and water cooling systems for induction furnaces. Furnace operators can increase the power supply utilization by the use of mechanical skimmers. The article describes the various lining materials used in induction furnaces, namely, silica, alumina, and magnesia. The crucible wall scrapers, ramming mixes, and lining push-out device used in induction furnaces are also reviewed. The article concludes with a discussion on batch operation and tap-and-charge operation, two distinct ways of operating a coreless induction furnace.