Inductors used for brazing can be machined from solid copper shapes or fabricated out of copper tubing, depending on the size and complexity of the braze joint geometry to be heated. This article provides information on inductors (coils) that are generally classified as solenoid, channel (slot), pancake, hairpin, butterfly, split-return, or internal coils. It discusses the variables pertinent to the design of inductors for brazing, soldering, or heat treating. The article presents various considerations for designing inductors for brazing of dissimilar materials that present a unique challenge in the field of induction brazing.

This article provides information on single-shot and scanning, the two types of induction heat treating processes that are based on whether the induction coil is moving relative to the part during the heating process. It describes the effect of the frequency of induction heating current on the induction coil and process design, and the control of heating in different areas of the inductor part. The article reviews three main tools for adjustment of coil design and fabrication: coupling gap, coil copper profile, and magnetic flux controllers. It examines the method of holding a part and presenting it to the inductor during the initial inductor design. The article provides information on coil leads/busswork and contacts that mechanically and electrically connect the induction coil head to the power supply. It concludes with a discussion on flux and oxide removal, leak and flow checking, silver plating, and electrical parameter measurement.

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 focuses on the frequently encountered causes of induction coil failures and typical failure modes in fabrication of hardening inductors, tooth-by-tooth gear-hardening inductors, clamshell inductors, contactless inductors, split-return inductors, butterfly inductors, and inductors for heating internal surfaces. It discusses the current density distribution and the skin effect, the proximity effect, and crack-propagation specifics. The article also describes selected properties of copper alloys, the electromagnetic edge effect of coil copper turn, and the effect of magnetic flux concentrators on coil life. It also reviews the importance of having appropriate and reliable electrical contacts.

Induction heat treatment is a common method for hardening and tempering of crankshafts, which are necessary components in almost every internal combustion engine for cars, trucks, and machinery, as well as pumps, compressors, and other devices. Similar to crankshafts, camshafts also belong to the same group of the critical engine/powertrain components. This article focuses on induction technologies used for surface hardening and tempering of automotive crankshafts, and provides general information on U-shaped inductors with crankshaft rotation and clamshell or split inductors without crankshaft rotation and their pros and cons. It also describes the effect of post-heat-treatment processes in crankshafts. The article concludes with a discussion on induction hardening of camshafts that focuses on those used in automobiles and truck engines.

Induction heating has the ability to concentrate the electromagnetic field and heat within a certain area of the workpiece. This article provides a detailed discussion on the end heating of bars, rods, and billets using solenoid inductors, oval inductors, and channel inductors. It reviews the importance of computer modeling in predicting the impact of different, interrelated, and nonlinear factors on the transitional and final thermal conditions of billets and bars. The article describes the most appropriate processes to improve end heating process effectiveness. Induction bending of narrow circumferential band of pipe or tube is also discussed. The article concludes with a discussion on stress relieving of pipe ends and welded areas.

Induction hardening of steel components is the most common application of induction heat treatment of steel. This article provides a detailed account of electromagnetic and thermal aspects of metallurgy of induction hardening of steels. It describes induction hardening techniques, namely, scan hardening, progressive hardening, single-shot hardening, and static hardening. The article discusses the techniques used to control the heat pattern, and provides a brief review of quenching techniques used in the induction hardening. It provides guidelines for selecting the frequency and power for induction hardening, and describes common methods for measuring case depth, such as optical and microhardness, and surface hardness. It provides information on some complications and ambiguities associated with these measurements. The article also discusses the commonly used non-destructive testing methods, namely, magnetic particle testing, ultrasonic testing, and eddy current testing to evaluate induction-hardened components.

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.

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.

Optimization plays a key role in the design of any structure or system, and electromagnetic devices are no exception. This article provides a description of the formulation of a design problem, and provides a review of the Paretian optimality. It focuses on nondominating sorting algorithms and multiobjective evolutionary strategy algorithms associated with evolutionary computing. The article provides information on field-based optimization problems. It also discusses the design of the pancake inductor that implies the solution of coupled electromagnetic and thermal fields, along with the use of optimal design procedures, to identify the best possible device or process.