Various types of furnaces have been used for cast iron melting. In terms of tonnage, the primary melting methods used by iron casting facilities are cupola and induction furnaces. This article describes the operation and control principles of cupola furnace. It discusses the advantages of specialized cupolas such as cokeless cupola and plasma-fired cupola. Melting in iron foundries is a major application of induction furnaces. The article describes the operations of two induction furnaces: the channel induction furnace and the induction crucible furnace. It explains the teapot principle of pressure-actuated pouring furnaces and provides information on the effect of pouring magnesium-treated melts.

The crucible induction furnace is growing as an alternative melting unit to the cupola furnace due to its low specific power and reduced power consumption during solid melting material. This article details the process engineering features of the crucible induction furnace. It discusses the various processes involved in melting, holding, and pouring of liquid melt in crucible induction furnaces wherein the holding operation is carried out in channel furnace and pouring operation in pressure-actuated pouring furnaces. The article examines the behavior of furnace refractory lining to defects such as erosion, infiltration, crack formation, and clogging, and the corresponding preventive measures to avoid the occurrence of these defects. It elucidates the overall furnace operations, including commissioning, operational procedures, automatic process monitoring, inductor change, and dealing with disturbances.

Crucible furnaces, as compared to electric arc furnaces, are increasingly deployed in various melting practices due to their environmental and workplace friendliness and their process benefits. This article focuses on the application of induction crucible furnaces for melting and pouring operations in small-and medium-sized steel foundries, including aluminum, copper, and zinc industries. It also provides information on the process engineering benefits of melting and pouring operations.

An induction channel furnace consists of a tiltable furnace vessel with refractory lining onto which an inductor or several inductors are flange mounted. This article includes a discussion on the design for holding and dosed-pouring of the iron melts, design for melting the materials, and refractory lining of furnace vessel. It provides information on the structural changes and refractory lining of channel inductors. The article also includes a discussion on power supplies deployed in channel inductor furnaces: line-frequency power supply for melting iron, and converter power supply for melting nonferrous metals. It concludes with an overview of the inductor cooling circuit.

This article discusses various molten-metal treatments, namely fluxing, degassing, and molten-metal filtration. It focuses on various molten-metal handling systems for transporting, holding, or delivering molten metal to the mold/die system. These include launders, tundishes, holding furnaces or transport crucibles, molten-metal transfer pumps, teeming ladles, and dosing and pouring furnaces.

In the metal producing and processing industries, induction melting and holding has found wide acceptance. This article provides a detailed account of the physical principles of induction melting processes. It discusses the fundamental principles and components of induction furnaces such as induction crucible furnaces, channel induction furnaces, and induction furnaces with cold crucible. The article describes the advantages, applications, and fundamental principles of induction skull melting. It also provides information on the various specific application-designed induction melting installations.

This article describes the casting characteristics and practices of copper and copper alloys. It discusses the melting and melt control of copper alloys, including various melt treatments to improve melt quality. These treatments include fluxing and metal refining, degassing, deoxidation, grain refining, and filtration. The article provides a discussion on these melt treatments for group I to III alloys. It describes the three categories of furnaces for melting copper casting alloys: crucible furnaces, open-flame furnaces, and induction furnaces. The article explains the important factors that influence the selection of a casting method. It discusses the production of copper alloy castings. The article concludes with information on the gating and feeding systems used in production of copper alloy castings.

Foundry practices critical to the production of cast irons include melting, alloying, molten metal treatment, pouring, and the design of feeding systems (gating and risering) to allow proper filling of the casting mold. This article reviews these production stages of iron foundry casting, with particular emphasis on the melting practices, molten metal treatment, and feeding of molten metal into sand molds. It discusses the castability factors, such as fluidity, shrinkage, and resistance, of gray iron. Typical cupola charge compositions and the final analyses for class 30 and class 40 gray iron castings are presented in a table. The article describes the induction melting and arc furnace melting used in gray iron foundries. It also reviews the inoculation methods such as stream inoculation and mold inoculation, of gray iron.

This article provides a comprehensive discussion on die casting alloy types and casting processes used in high-pressure die casting. It presents the advantages and disadvantages of high-pressure die casting and describes the product design for the process. The article concludes with information on the metal injection process of high-pressure die casting.

Nearly two-thirds of the aluminum castings made in North America are produced using high-pressure die casting techniques. This article compares and contrasts traditional high-pressure die casting with an improved version that uses a vacuum to pull air out of the die in order to reduce porosity in as-cast parts. It begins by describing a typical cycle for a traditional cold-chamber die casting machine, using detailed illustrations to show how gas can become trapped in the liquid metal. It then presents various remedies, ultimately focusing on vacuum die casting for the production of high-integrity parts. In addition to vacuum technology, the article discusses casting alloys, dies, and cells, and describes some of the benefits of structural die castings.

Metal-matrix composites (MMCs) are a class of materials with a wide variety of structural, wear, and thermal management applications. This article discusses the primary processing methods used to manufacture discontinuous aluminum MMCs, namely, high-pressure die casting, pressure infiltration casting, liquid metal infiltration, spray deposition, and powder metallurgy methods. It describes the processing of continuous fiber-reinforced aluminum, discontinuously, reinforced titanium, and continuous fiber-reinforced titanium. The article concludes with information on work done to develop magnesium, copper, and superalloy MMCs.

Aluminum casting alloys are among the most versatile of all common foundry alloys and generally have high castability ratings. This article provides an overview of the common methods of aluminum shape casting. It discusses the designations of aluminum casting alloys categorized by the Aluminum Association designation system. The article summarizes the basic composition groupings of aluminum casting alloy and discusses the effects of specific alloying elements and impurities. The characteristics of the important casting processes are summarized and compared in a table. The article presents the advantages and disadvantages of green sand casting, permanent mold casting, semipermanent mold casting, and high-pressure die casting. A discussion on other casting processes, such as investment casting, lost foam, plaster mold casting, pressure casting, centrifugal casting, and semisolid casting, is also included.

The information provided in this article is intended for those individuals who want to determine why a casting component failed to perform its intended purpose. It is also intended to provide insights for potential casting applications so that the likelihood of failure to perform the intended function is decreased. The article addresses factors that may cause failures in castings for each metal type, starting with gray iron and progressing to ductile iron, steel, aluminum, and copper-base alloys. It describes the general root causes of failure attributed to the casting material, production method, and/or design. The article also addresses conditions related to the casting process but not specific to any metal group, including misruns, pour shorts, broken cores, and foundry expertise. The discussion in each casting metal group includes factors concerning defects that can occur specific to the metal group and progress from melting to solidification, casting processing, and finally how the removal of the mold material can affect performance.

This article presents a detailed account on the process flow, composition, alternative sources, and the advancement of ironmaking, steelmaking and secondary steelmaking practices. Some steels, such as bearing steels, heat-resistant steels, ultrahigh strength missile and aircraft steels, and rotor steels have higher quality requirements and tighter composition control than plain carbon or ordinary low-alloy steels. The production of special-quality steels requires vacuum-based induction or electric remelting and refining capabilities. The article explores the types and characteristics of various steel manufacturing processes, such as ingot casting, continuous casting, and hot rolling. It provides an outline of specialized processing routes of producing ultralow plain carbon steels, interstitial-free steels, high strength low-alloy steels, ultrahigh strength steels, stainless steels, and cold-rolled products, and briefly explains the analytical techniques for liquid steels.

This article focuses on the general root causes of failure attributed to the casting process, casting material, and design with examples. The casting processes discussed include gravity die casting, pressure die casting, semisolid casting, squeeze casting, and centrifugal casting. Cast iron, gray cast iron, malleable irons, ductile iron, low-alloy steel castings, austenitic steels, corrosion-resistant castings, and cast aluminum alloys are the materials discussed. The article describes the general types of discontinuities or imperfections for traditional casting with sand molds. It presents the international classification of common casting defects in a tabular form.

This article focuses on the construction, operation of electric arc furnaces (EAF), and their auxiliary equipment in the steel foundry industry. It provides information on the power supply of EAF and discusses the components of the EAF, including the roof, furnace shell, spout and tap hole, water-cooling system, preheat and furnace scrap burners, and ladles. The article describes the acid and basic steelmaking practices. It discusses the raw materials used, oxidation process, methods of heat reduction, and deoxidation process in the practices. The article provides a discussion on the arc melting of iron and EAF steelmaking.

This article provides a detailed discussion on the components of a high-performance induction crucible furnace system, namely, furnace body, power supply, and peripheral components. The furnace body contains refractory lining, coil and transformer yokes, and tilting frame and furnace cover. The power supply consists of the following: transformers, frequency converters, capacitor banks, and power cables and furnace coils. The peripheral components comprise recooling device, charging system, and skimming devices. The article also presents a three-dimensional representation of the induction crucible furnace system.