Tapping is a machining process for producing internal threads. This article provides a discussion on machines and accessories of tapping. It reviews the seven categories of taps, namely, solid, shell, sectional, expansion, inserted-chaser, adjustable, and collapsible taps, as well as their design and functions. It explains the influences of various factors on the selection of tap design features and discusses the principal factors that influence the selection of equipment and procedure for tapping. The article reviews the factors that determine torque demand. It also provides an overview of tap materials and surface treatment and concludes with a discussion on tapping of taper pipe threads.

This article discusses various machining techniques of zinc alloy die castings. These include turning, boring, drilling, reaming, tapping, die threading, milling, and sawing. In addition, the article describes the factors that influence machinability of the zinc alloy die castings.

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.

This article describes the methods for determining the flow rate of metal powders. It examines the factors affecting flow rate, apparent density, and angle of repose of metal powders. The article reviews the frictional properties, cohesive strength, frictional properties, tap density, and compressibility of metal powders. It explains the mechanisms of powder segregation. The article provides information on green strength and springback value of rectangular test bar. It concludes with a discussion on the chemical composition of metal powders.

This article begins with a discussion on the classification of aluminum alloys and the selection of alloy and temper based on machinability. It provides an overview of cutting force and power, tool design and material, and general machining conditions. In addition, the article discusses distortion and dimensional variation and machining problems during the machining of high-silicon aluminum alloy. It also provides information on tool design and material, speed and feed, and the cutting fluid used for various machining processes, namely, turning, boring, planing and shaping, broaching, reaming, tapping, milling, sawing, grinding, honing, and lapping. The article concludes with a discussion on drilling operations in automatic bar and chucking machines and drill presses.

This article presents a detailed account of the welding parameters, equipment needed, applications, advantages, limitations, and the process variables affecting various types of resistance welding operations, namely, resistance spot welding, resistance seam welding, resistance projection welding, and flash welding.

This article describes the unique aspects of cold isostatic pressing (CIP) in comparison with die compaction, for powder metallurgy parts. It details the components of CIP equipment, including pressure vessels, pressure generators, and tooling material. The article reviews the part shapes and their influence in determining tap density of the filled mold. It provides a discussion on process parameters, such as dwell time, depressurization rate, evaluation of green strength and density, and thermal processing, and illustrates a process flowchart for the production of CIP parts.

This article summarizes sampling of powders, which includes the sampling of stored material and flowing streams, sample reduction and evaluation, and weight of sample required. It also summarizes the classification of powders. Classifiers are divided into two categories: counterflow equilibrium and crossflow separation. Classification methods are used to exclude certain powder sizes from a powder distribution and to obtain particular powder distributions. For example, sieving methods are used to obtain particular powder distributions and to obtain narrow size ranges of a powder. The article summarizes the sieving methods for powders. The sieving methods include hand sieving, machine sieving, manual wet sieving, air jet sieving, sonic sifter, wet sieving by machine, the Seishin robot sifter, automated systems, and ultrasonic machine sieving. The article outlines the sieve types and the process variables of the sieving process. An appendix reviews dispersion of powders in liquids.

Tin is produced from both primary and secondary sources. This article discusses the chemical compositions, production, properties, microstructure and applications of tin and tin alloys. The major tin alloys discussed here are tin-antimony-copper alloy (pewter), bearing alloy, solder alloy and other alloys containing traces of tin. Data on tin consumption in the United States is presented graphically.

Cast iron, which usually refers to an in situ composite of stable eutectic graphite in a steel matrix, includes the major classifications of gray iron, ductile iron, compacted graphite iron, malleable iron, and white iron. This article discusses melting, pouring, desulfurization, inoculation, alloying, and melt treatment of these major ferrous alloys as well as carbon and alloy steels. It explains the principles of solidification by describing the iron-carbon phase diagram, and provides a pictorial presentation of the basic microstructures and processing steps for cast irons.

This article discusses the principles of operation, equipment needed, applications, and advantages and disadvantages of various fusion welding processes, namely, oxyfuel gas welding, electron beam welding, stud welding, laser beam welding, percussion welding, high-frequency welding, and thermite welding.

Ferromagnetic resonance (FMR) is used in the identification of the magnetic state of materials, the quantitative determination of static magnetic parameters, and the determination of microwave losses. This article describes the theory of ferromagnetic resonance and provides information on reflection spectrometers, microwave spectrometers, and ferromagnetic anti-resonance spectrometers used for measuring FMR. It also discusses the applications of FMR and provides several detailed examples.

Tin is a soft, brilliant white, low-melting metal that is most widely known and characterized in the form of coating. This article discusses the primary and secondary production of tin and explains the uses of tin in coating, namely tinplating, electroplating, and hot dip coatings. It presents a short note on pure (unalloyed) tin and uses of tin in chemicals. The article also covers the compositions and uses of tin alloys which include solders, pewter, bearing alloys, alloys for organ pipes, and fusible alloys. It goes on to discuss the other alloys containing tin including battery grid alloys, type metals, copper alloys, dental alloys, cast irons, titanium alloys, and zirconium alloys. Finally, it presents a short note on the applications of tin powder and corrosion resistance of tin.

This article reviews the 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 molten metal treatments for high-silicon gray, high-nickel ductile, and malleable irons. Foundry practices are also described for compacted graphite, high-silicon ductile, and high-alloy white irons.

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.

The recreation industry covers a huge number of sports, games, and activities that take place in environments as diverse as the activities themselves. This article addresses the corrosive attack on recreational equipment, such as recreational boats, firearms, bicycles, playground equipment, and climbing gear. It discusses the procedures for base materials selection, surface treatments and coatings, and good practice of maintenance to mitigate corrosion while addressing other functional issues for a given piece of equipment.

Cores are separate shapes of sand that are placed in the mold to provide castings with contours, cavities, and passages that are not otherwise practical or physically obtainable by the mold. This article describes the basic principles of coremaking and the types of core sands, binders, and additives used in coremaking. It discusses the curing of compacted cores by core baking and the hot box processes. The article provides an overview of the core coatings, assembling and core setting, coring of tortuous passages, and cores in permanent mold castings and investment castings. It also discusses the design considerations in coremaking to eliminate cores and compares coring with drilling.

Sand mold and permanent mold casting are the major methods for shape casting of steels, with production closely split among green sand, chemically bonded sand, and permanent mold processes. This article describes key aspects of the steel casting process, including steel solidification characteristics, melting practices, melt treatment, and feeding of the molten steel into the mold used in steel foundries. It discusses the features of melting furnaces used in direct arc melting and induction melting. It reviews factors such as wall thickness and designing for avoidance of hot spots. The article explains the sand casting and permanent mold casting of steel. The process design and casting of thin sections are also discussed.